ObjectiveTo investigate the short-term knee function recovery of patients undergoing total knee arthroplasty (TKA) after discharge and analyze its related factors. MethodsFrom December, 2022 to April, 2023, 140 adult patients who underwent TKA in Nanjing Drum Tower Hospital and being about to be discharged were selected as the survey subjects using convenient sampling. Potential influencing factors were selected based on a literature review. They were investigated with general information questionnaire, Rehabilitation Exercise Compliance Scale, Self-Efficacy Scale for Rehabilitation Exercise (SER), Visual Analog Scale for pain (VAS), and joint range of motion measurements before discharge, and were investigated with the Hospital for Special Surgery Knee Score (HSS) one month after discharge. ResultsA total of 130 patients finished follow-up. One month after discharge, the HSS score ranged from 40 to 82, with an average of (70.89±6.26). Multiple linear regression analysis revealed that Body Mass Index (B = -0.423, 95%CI -0.622 to -0.224, P < 0.001), pre-discharge VAS (B = -1.016, 95%CI -1.198 to -0.113, P = 0.028), rehabilitation exercise compliance (B = 0.267, 95%CI 0.121 to 0.413, P < 0.001), SER (B = 0.478, 95%CI 0.315 to 0.642, P < 0.001), and knee joint flexion contracture angle (B = -0.251, 95%CI -0.414 to -0.088, P = 0.003) could influence HSS score one month after discharge (R² = 0.615, F =17.106, P < 0.001). ConclusionPatients after TKA have recovered well in short time after discharge, however, there is still significant room for improvement. Clinical healthcare providers should design and implement appropriate interventions based on related factors to improve the function.