[Objective] To compare the effects of high tibial osteotomy (HTO) , unicompartmental knee arthroplasty (UKA) and total knee arthroplasty (TKA) on coagulation fibrinolytic system and clinical outcomes for knee osteoarthritis (KOA) . [Methods] A retrospective study was conducted on 99 patients who received surgical treatment for medial KOA in our hospital from January 2015 to December 2018. According to preoperative doctor-patient communication, 34 patients received HTO, 33 patients underwent UKA, and 32 patients were treat- ed with TKA. The documents regarding to coagulation-fibrinolytic system and clinical consequences were compared. [Results] Compared with those preoperatively, the PT, APTT, FDP and D-D significantly increased in all the three groups 1 day after operation (P<0.05) , and then returned to the preoperative level at 7 days after operation (P>0.05) . At 1 day after operation, PT, APTT, FDP and D-D were ranked from low to high in the following order: UKA group < HTO group HTO group > TKA group, with statistically significant differences (P<0.05) , whereas which became not statistically significant among the three groups at 2 years after operation (P>0.05) . [Conclusion] The three surgical procedures for treatment of medial compartment KOA is comparable in the middle and long-term outcomes, however, the UKA is better than HTO and TKA in short-term outcomes with little impact on the coagulation system.