Background: Although numerous surgical techniques have been described and deployed, flexor tenolysis remains one of the most challenging procedures in hand surgery and there is no standardised way of recording the outcomes. The aim of this study is to systematically review the evidence supporting current concepts and outcomes in flexor tenolysis. Methods: The systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Medline and EMBASE databases were searched for articles published in English using the keyword search terms ‘flexor’ or ‘tendon’ and ‘tenolysis’ or ‘tenoarthrolysis’. A total of 555 articles were listed and further screening provided fourteen studies remaining for final inclusion. The parameters for data extraction included number of digits operated on, age of the patients, initial injury mechanism requiring flexor tenolysis, outcome assessment method, follow-up period, results and complications. The primary outcome was postoperative active range of motion. Results: 556 digits were included across all studies and the age of patients ranged between 1 and 75 years. Eleven out of fourteen of the articles used the Strickland criteria to report their outcomes. Other outcome measures used were total active motion (TAM), Buck-Gramcko and pulp-to-palm distance. In the studies which used the Strickland criteria, the average percentage of outcomes reported as ‘good’ or ‘excellent’ was 68% with a range between 45% and 91%. Three other studies used Buck-Gramcko, TAM and pulp-to-palm distance outcome reporting and achieved 72% ‘good’ or ‘excellent’, 84% improvement and 30% able to touch distal palm crease respectively. Conclusions: Although the literature contains a limited number of observational studies, the current evidence shows that 68% of well-selected patients who undergo flexor tenolysis achieve a good or excellent outcome as measured by the Strickland criteria. Level of Evidence: Level III (Therapeutic)