Giao duc trung hoc (tieng Anh: secondary education) la giai đoan giao duc dien ra trong cac truong trung hoc, theo sau giao duc tieu hoc. O hau het cac quoc gia, giao duc trung hoc thuoc giai đoan giao duc bat buoc, trong khi o mot so quoc gia khac thi chi co giao duc tieu hoc hay giao duc co ban moi mang tinh chat bat buoc.
O Viet Nam, giao duc trung hoc va giao duc tieu hoc nam trong giai đoan goi la giao duc pho thong. Giao duc trung hoc con đuoc chia ra lam hai bac: trung hoc co so va trung hoc pho thong: Giao duc trung hoc co so keo dai bon nam hoc, tu lop sau đen lop chin. Đieu kien đe vao lop sau la hoc sinh phai hoan thanh chuong trinh tieu hoc. Giao duc trung hoc co so nham giup hoc sinh cung co va phat trien nhung ket qua cua giao duc tieu hoc; co trinh đo hoc van pho thong co so va nhung hieu biet ban đau ve ki thuat va huong nghiep đe tiep tuc hoc trung hoc pho thong, trung hoc chuyen nghiep, hoc nghe hoac đi vao cuoc song lao đong. Giao duc trung hoc pho thong co thoi gian ba nam hoc, tu lop muoi đen lop muoi hai. Đe vao lop muoi hoc sinh phai tot nghiep trung hoc co so. Giao duc trung hoc pho thong nham giup hoc sinh cung co va phat trien nhung ket qua cua giao duc trung hoc co so, hoan thien hoc van pho thong va nhung hieu biet thong thuong ve ki thuat va huong nghiep đe tiep tuc hoc đai hoc, cao đang, trung hoc chuyen nghiep, hoc nghe, hoac đi vao cuoc song lao đong. Chuong trinh đai hoc  thuong keo dai toi đa 4 nam hoc va chi keo dai 1.5 nam khi đa hoc cao đang, cao đang hoc lau hon 1 nam khi khong hoc bac trung cap, trung cap hoc keo dai lau hon toi đa 10 thang sau khi tot nghiep bac trung hoc pho thong, tuy tung truong ma thoi gian hoc se keo dai lau hon hoac cham hon so voi thoi gian hoc cua nhung truong hoc chuan quoc gia..


Đinh nghia Giao duc trung hoc o hau het cac quoc gia la mot giai đoan trong qua trinh giao duc lien tuc bat buoc, chiu trach nhiem cho su phat trien cua tre trong đo tuoi thieu nien, giai đoan phat trien nhanh nhat ve the chat, tinh than va cam xuc. Cap đo giao duc nay la noi cac gia tri va thai đo hinh thanh o truong tieu hoc đa an sau hon cung voi viec tiep thu kien thuc va ky nang moi.
—  Theo UNESCO, Secondary Education Reform: Towards a Convergence of Knowledge Acquisition and Skills Development, 2005
Phan loai giao duc tieu chuan quoc te nam 1997 (ISCED) mo ta bay cap đo co the đuoc su dung đe so sanh ve giao duc quoc te. Voi moi quoc gia, nhung cap đo nay co the đuoc thuc hien theo nhung cach khac nhau, voi cac đo tuoi khac nhau:

Cap đo 0 - Giao duc mam non
Cap đo 1 - Giao duc tieu hoc hoac giai đoan đau cua giao duc co ban
Cap đo 2 - Trung hoc co so hoac giai đoan thu hai cua giao duc co ban
Cap đo 3 - Trung hoc pho thong
Cap đo 4 - Giao duc sau trung hoc
Cap đo 5 - Giai đoan đau tien cua giao duc đai hoc
Cap đo 6 - Giai đoan thu hai cua giao duc đai hoc
Trong he thong nay, Cap 1 va 2 - nghia la giao duc tieu hoc va trung hoc co so - cung nhau hinh thanh giao duc co ban.
Ngoai ra, cac quoc gia co the gan nhan giao duc trung hoc tu cap 2 đen cap 4 voi nhau, cap 2 va cap 3 hoac cap 2 mot minh. Cac đinh nghia cap đo nay đuoc đat cung nhau cho muc đich thong ke va cho phep thu thap du lieu so sanh trong nuoc va quoc te. Chung đa đuoc Đai hoi đong UNESCO phe chuan tai phien hop thu 29 vao thang 11 nam 1997.
Su khoi đau cua giao duc trung hoc co so đuoc đac trung boi su chuyen đoi tu mot giao vien quan ly mot lop (giao vien cung cap tat ca noi dung cho mot nhom hoc sinh) đen moi giao vien phu trach mot mon hoc. Muc đich giao duc cua no la hoan thanh viec cung cap giao duc co ban (tu đo hoan thanh viec cung cap cac ky nang co ban) va đat nen mong cho viec hoc tap suot đoi.
Giao duc trung hoc co so co cac tieu chi sau:

Đau vao sau 6 nam hoc tieu hoc (5 nam tieu hoc voi mot so quoc gia)
Giao vien chi giang day trong chuyen mon cua ho.
Tiep tuc cac khoa hoc cap 3, hoac giao duc nghe nghiep, hoac viec lam sau 9 nam hoac hon tong so nam hoc.
Su ket thuc cua giao duc trung hoc co so thuong trung voi su ket thuc cua giao duc bat buoc tai mot so quoc gia.
(Cao trung) giao duc trung hoc pho thong bat đau khi hoan thanh giao duc co ban, cung co nghia la hoan thanh giao duc trung hoc co so. Trong tam giao duc rat đa dang tuy theo so thich va đinh huong tuong lai cua hoc sinh. Giao duc o cap đo nay thuong la tu nguyen.
(Cao trung) giao duc trung hoc pho thong co cac tieu chi sau:

Đau vao sau 9 nam hoc co ban
Tuoi đien hinh khi nhap hoc la tu 14 đen 16 tuoi
Tat ca cac giao vien co trinh đo cap 5 trong mon hoc ho đang giang day
tiep tuc cac khoa hoc cap 4 hoac 5 hoac đen viec lam truc tiep.
Hoan thanh giao duc trung hoc pho thong (Cao trung) cung cap cac yeu cau đau vao cho giao duc đai hoc cap 5, cac yeu cau đau vao cho giao duc ky thuat hoac day nghe (Cap đo 4, khoa hoc đai hoc), hoac truc tiep vao noi lam viec.
Thuat ngu cho cac truong trung hoc thay đoi theo tung quoc gia khac nhau.Cac truong trung hoc cung co the đuoc goi la hoc vien, cao đang, the duc, truong trung hoc co so, lyceums, truong trung hoc pho thong, truong du bi, truong trung hoc, hoac truong day nghe,... Đe biet them thong tin ve danh phap, xem phan ben duoi theo quoc gia.


= Thuat ngu giao duc trung hoc tai cac quoc gia =
Argentina: secundaria hoac polimodal, escuela secundaria
Australia: high school, secondary college
Austria: Gymnasium (Ober- & Unterstufe), Hauptschule, Hohere Bundeslehranstalt (HBLA), Hohere Technische Lehranstalt (HTL)
Azerbaijan: orta məktəb
Bahamas, The: junior high (Lop 7–9), senior high (Lop 10–12)
Belgium: lagere school/ecole primaire, secundair onderwijs/ecole secondaire, humaniora/humanites
Bolivia: educacion primaria superior (Lop 6–8) and educacion secundaria, (Lop 9–12)
Bosnia and Herzegovina: srednja skola (literally middle school), gimnazija (gymnasium)
Brazil: ensino medio, segundo grau
Brunei: mostly sekolah menengah (secondary school), a few maktab (college)
Bulgaria: cредно образование (Lop 8–12)
Canada: High school, junior high hoac middle school, secondary school, ecole secondaire, collegiate institute, polyvalente
Chile: ensenanza media
China: zhong xue (中学; literally, middle school), consisting of chu zhong (初中; 初级中学; literally low-level middle school) tu lop 7 đen lop 9 va gao zhong (高中; 高级中学; literally high-level middle school) Lop 10 - 12
Colombia: bachillerato, segunda ensenanza (literally second learning)
Croatia: srednja skola (literally middle school), gimnazija (gymnasium)
Cyprus: Γυμνασιο (gymnasium), Ενιαιο Λυκειο (Lyceum)
Czech Republic: stredni skola (literally middle school), gymnazium (gymnasium), stredni odborne uciliste
Denmark: gymnasium
Dominican Republic: nivel medio, bachillerato
Egypt: Thanawya Amma (ثانوية عامة), (Chung chi trung hoc cong lap)
Estonia: upper secondary school, gymnasium, Lyceum
Finland: lukio (Finn.) gymnasium (Swed.)
France: college (junior), lycee (senior)
Germany: Gymnasium, Gesamtschule, Realschule, Hauptschule, Fachoberschule
Greece: Γυμνασιο (3 nam), Γενικο Λυκειο (3 nam) (~1996, 2006~ hien tai), Ενιαιο Λυκειο (3 nam), (1997~2006) (lyceum)
Hong Kong: Secondary school (中學)
Hungary: gimnazium (grammar school), kozepiskola (comprehensive school, "middle-school"), szakkozepiskola (vocational secondary school, "specified middle-school")
Iceland: framhaldsskoli (menntaskoli, iðnskoli, fjolbrautaskoli) from 11-13 Grade. You go first in 1 - 10 Grade then you change the school to Menntaskola and take 3 years (11-13 Grade). But you can also take it 4 years.
India: secondary school, higher secondary school
Indonesia: sekolah menengah atas (SMA) (lit. "upper middle school"), sekolah menengah pertama (SMP) (lit. "first middle school"), sekolah menengah kejuruan (SMK) (vocational school, lit. "middle vocational school")
Ireland: Meanscoil or Secondary School
Iran: Madrese Rahnamaie (مدرسه راهنمایی), (public secondary certificate)
Israel: Bet Sefer Tichon (בית ספר תיכון) (literally middle school, but in reality grades 9-12)
Italy: scuola secondaria di primo grado (3 years) + scuola secondaria di secondo grado (5 years): Liceo, Istituto Tecnico and Istituto professionale
Nhat Ban: chugakko (中学校; literally middle school), kotogakko (高等学校; literally high school), chutokyoikugakko (中等教育学校; Secondary School) "chusei"
Latvia: vidusskola (literally middle school)
Liechtenstein: gymnasium
Lithuania: vidurine mokykla (literally middle school), gimnazija (gymnasium), licejus (lyceum)
Malaysia: secondary school or sekolah menengah, sometimes high school is used
Malta: skola sekondarja or secondary school
Mexico: educacion secundaria y preparatoria
Mongolia: бүрэн дунд сургууль
Netherlands: middelbare school or voortgezet onderwijs
New Zealand: high school, college or secondary school
Nigeria: Secondary school, Junior or senior secondary school
Norway: videregaende skole
Pakistan: secondary school, higher secondary school
Paraguay: educacion media
Peru: educacion secundaria or escuela secundaria
Philippines: high school or mataas na paaralan
Poland: liceum (grades 9–12)
Portugal: 2º Ciclo do Ensino Basico (5th and 6th grades), 3º Ciclo do Ensino Basico (7th to 9th grades), and Ensino Secundario, Liceu (10th to 12th grades)
Romania: gimnaziu (grades 5–8), liceu (grades 9–12)
Russia: средняя школа (literally middle school); grades 5–9 junior middle school (compulsory), grades 10–11 senior middle school (voluntary)
Serbia: gymnasium (4 years), professional schools (4 years), vocational schools (3 or 4 years)
South Africa: High School or Hoerskool
South Korea: 중고등학교(中高等學校・Chung'godunghakkyo), 중등교육 (Chungdung'gyoyuk; literally middle education), comprising 중학교 (Chunghakkyo; the Lower secondary school, years 7–9, though referred to as "middle school grades 1–3") and 고등학교 (Kodunghakkyo; the Upper secondary school, years 10–12, though referred to as "high school grades 1–3")
Spain: educacion secundaria, composed of two cycles: E.S.O. (Educacion Secundaria Obligatoria, compulsory secondary education, 4 years, 7th to 10th grade) and bachillerato (non-compulsory secondary education, 2 years, 11th and 12th grade); formerly, primary education comprised up to the 8th grade and the secondary education was composed of two non-compulsory cycles: B.U.P. (Bachillerato Unificado Polivalente, 3 years, 9th to 11th grade) and C.O.U. (Curso de Orientacion Universitaria, 1 year, 12th grade)
Sri Lanka: junior secondary school, senior secondary school
Sweden: gymnasium
Switzerland: gymnasium, secondary school, college or lycee
Taiwan: Junior High School (國民中學), Senior High School (高級中學), Vocational High School (高級職業中學), Military School (軍校), and Complete High School (完全中學).
Thailand: matthayommasueksa (มัธยมศึกษา; lit. "Secondary education")
Trinidad and Tobago: Secondary School, Forms 1 to 5 (5 years) or Forms 1-6 (7 years)
Turkey: Lise
Ukraine: середня школа (literally middle school); grades 5–9 junior middle school (compulsory), grades 10–12 senior middle school (voluntary)
United Kingdom: Secondary School (tuong đuong voi High School)
United States: High school (North America) (usually grades 9–12 but sometimes 10–12, it is also called senior high school) is always considered secondary education; junior high school or intermediate school or middle school (6–8, 7–8, 6–9, 7–9, or other variations) are sometimes considered secondary education.
Uruguay: Liceo hoac Secundaria (3 nam giao duc bat buoc: Ciclo Basico; va 3 nam chuyen mon: Bachillerato Diversificado, into: Humanities (Law or Economics), Biology (Medicine or Agronomy), Science (Engineering or Architecture), and Art
Venezuela: bachillerato
Viet Nam: Trung hoc co so (THCS, "basic middle school", tuong đuong junior high school o My.); trung hoc pho thong (THPT, "general middle school", tuong đuong senior high school o My)


Ghi chu Lien ket ngoai Tu lieu lien quan toi Secondary education tai Wikimedia Commons
Giao duc trung hoc Luu tru ngay 15 thang 12 nam 2013 tai Wayback Machine. Bo Giao duc va Đao tao (Viet Nam).