Objective. To explore the safety of total knee arthroplasty (TKA) in the treatment of knee osteoarthritis (KOA) and its impact on patients’ postoperative pain and quality of life. Methods. A total of 60 KOA patients admitted to our hospital from January 2019 to January 2020 were selected as the research objects. The knee joint scores (HSS) before and after TKA were compared, and the patients’ quality of life was evaluated using the Osteoarthritis Index of Western Ontario and McMaster University (WOMAC). At the same time, the number of patients with complications was recorded, and the efficacy of TKA was comprehensively analyzed. Results. The postoperative HSS score was significantly higher than the preoperative score (
P
<
0.05
), the postoperative pain score increased with time, and the pain gradually decreased. The postoperative WOMAC score was significantly lower than the preoperative score (
P
<
0.001
), and the score at 6 months after surgery was significantly lower than that at 3 months after surgery (
P
<
0.001
). There were no complications such as severe prosthesis fracture, secondary sepsis, and patellar tendon rupture, and the total incidence of complications was 11.7%. The effective rate of treatment at 6 months after operation was 98.3%, which was significantly higher than that at 3 months after operation (
P
<
0.05
). Conclusion. Total knee arthroplasty can improve the knee joint function of patients with knee osteoarthritis, with low postoperative pain, low complication rate, and good quality of life for patients. It is worthy of promotion and application.