Objective To investigate preoperative outcome expectations among patients undergoing total knee arthroplasty, and to analyze its influencing factors. Methods A total of 198 patients undergoing total knee arthroplasty were investigated using the Western Ontario and McMaster Universities Osteoarthritis Index and Hospital for Special Surgery Total knee Replacement Expectations Survey. Results The mean score of preoperative outcome expectations among the patients was 89.17±13.89.Multivariate stepwise regression analysis showed that, patient age, living companions and preoperative joint functional activity score level were the main influencing factors of preoperative outcome expectations (P＜0.01 for all). Conclusion The preoperative outcome expectations among the patients undergoing total knee arthroplasty is at a high level.It is necessary to strengthen the assessment and management of preoperative expectations, so as to enhance patient satisfaction and improve the relationship between clients and medical staff.