MSA可能指：

組織或企業

馬來西亞-新加坡航空：新加坡航空及馬來西亞航空的前身。
交通運輸部海事局（China Maritime Safety Administration）
海上保安廳（舊稱Maritime Safety Agency，今稱Japan Coast Guard）
, aka the Pakistan Coast Guard
Masonic Service Association, a Freemasonry publishing resource
, a society for the promotion of microscopy
, a manufacturer of industrial safety clothing and equipment
, an organization for the advancement of mineralogy
Motion Sensing Alliance, an alliance for the development of motion sensing technology
, the governing body for motorsport in the United Kingdom
Mutual Security Agency, established by the US  (1951), and distributed aid to Europe after the Marshall Plan
, a society promoting the study of fungi

教育

學位
 Master of Accountancy, an accounting degree
 , a degree providing preparation for administrative positions

學校
 , an architecture school in Glasgow, Scotland
 , an architecture school in Manchester, England
 Maryland School of the Arts, a fictional dance school in the film Step Up
 , an evaluation and accreditation association 
 , a school in Minnesota
 , a high school in Brookhaven, Mississippi
 , a summer program at the University of Missouri
 , a culinary arts institute in Istanbul, Turkey
 , a university in October City, Egypt
 , the student government association of Monash University, Melbourne, Australia
 , a group dedicated to Islamic societies on college campuses in Canada and the United States

科學及醫學 
 5-甲氧基水杨酸（5-Methoxysalicylic acid）：一种化合物，在MALDI质谱中用作基质。
 甘露醇鹽瓊脂（Mannitol salt agar）：一種微生物培養基。
 , the analysis of the process of obtaining measurements
 甲基磺酸（Methanesulfonic acid）
 , a period of African prehistory
 多重序列比對（Multiple sequence alignment）是對三個以上的生物學序列，如蛋白質序列、DNA序列或RNA序列所作的序列比對。
 , a degenerative neurological disorder
 Multiscale approximation 或多解析度分析（multiresolution analysis）
  (linguistics)
 , a quality criterion for a correlation matrix as prequisition for factor analysis (statistics)

科技 
 , the primary storage device for some data centres
 , a computer program used when sending email
 , a master agreement defining services to be delivered
 Microsoft Access：一種資料庫管理系統
 , a combination of Java ME extensions
 MSA，MIPS SIMD 架构 
 , an agreement between multiple manufacturers to make products which are compatible across vendors

運輸 
 MSA , a steam engine class of the Western Australian Government Railways
 公路服務區（Motorway service area）
 , an airport at Muskrat Dam, Ontario, Canada (IATA code)

其他
 馬來語（Malay language）
, a licensing contract between local authorities in the United Kingdom and suppliers of geographic data 
 , 2009 United States federal hate-crime legislation
, an indoor arena in Indianapolis, Indiana demolished in 2001
, a tax-deferred deposit account for medical expenses
, a geographical area associated with an urban area of 50,000 people or more, as defined by the United States Office of Management and Budget
, a geographical area associated with an urban area of 10,000 to 49,999 people, as defined by the United States Office of Management and Budget
, used for safely navigating aircraft over terrain or large structures
現代標準阿拉伯語（Modern Standard Arabic）
, an agreement reached between U.S. States and major tobacco companies
MSA Kyotei, a Japanese abbreviation in reference to .
 Minesweeper Auxiliary

三字拉丁字母縮寫消歧義