Inclusion Criteria:  Age between 18 to 75 years old (including 18 and 75) Agreeing to sign the written informed consents Diagnosed as peripheral T-cell lymphoma, including peripheral T-cell lymphoma, unspecified type, anaplastic large cell lymphoma (ALK negative or positive), angioimmunoblastic T-cell lymphoma, enteropathy Related T-cell lymphoma, hepatosplenic T-cell lymphoma, γ/δ T-cell lymphoma, NK/T-cell lymphoma, and other subtypes of PTCL that the investigator judges to be suitable for participating in this study Received at least first-line anti-tumor therapy in the past, whether or not Chidamide has been used Having at least one measurable lesions World health organization-Eastern Cooperative Oncology Group Performance Status (ECOG) 0-2 Life expectancy no less than 3 months enough main organ function Pregnancy test within 7 days must be negative for women of childbearing period, and appropriate measures should be taken for contraception for women in childbearing period during the study and six months after this study Agreeing to follow the trail protocol requirements  Exclusion Criteria:  Types other than peripheral T-cell lymphoma listed in the enrollment criteria Diagnosed as central nervous system lymphoma Received palliative treatment for other malignant tumors in the past 2 years Uncontrolled active infection Congestive heart failure, uncontrolled coronary heart disease, arrhythmia and heart infarction less than 6 months The non-hematological toxicity caused by the previous anti-tumor treatment has not recovered to ≤1 grade, and the hematological toxicity has not recovered to ≤2 grade Patients with a history of mental illness Those who are known to be allergic to the active ingredients or excipients of the drug parsaclisib and chidamide Received PI3Kδ inhibitor treatment in the past Received autologous hematopoietic or allogeneic hematopoietic stem cell transplantation within 3 months World health organization-Eastern Cooperative Oncology Group Performance Status (ECOG) >2 There are factors that affect the absorption of oral drugs Pregnant or lactating women Researchers determine unsuited to participate in this trial