Objective To explore the application value of the lower limbs robot-assisted training system for post-total knee arthroplasty (TKA) rehabilitation. Methods A total of 96 patients following TKA were assigned into a control group or an observation group chronologically, with 48 in each group.The control group was given traditional manual rehabilitation therapy, while the observation group received robot-assisted lower limbs rehabilitation.The active and passive knee range of motion (ROM), the Hospital for Special Surgery (HSS) knee score, the Modified Barthel Index (MBI) score, length of hospital stay and hospitalization expense were compared between the two groups after the intervention. Results The observation group had greater active and passive knee ROM, higher HSS knee score and MBI score, whereas shorter length of hospital stay and less hospitalization expense compared with the control group （P＜0.05,P＜0.01）. Conclusion The application of robotic system for lower limbs rehabilitation can promote recovery of knee function after TKA.