Abstract: Objective To investigate the effect of intra-articular injection of autologous bone marrow mesenchymal stem cells combined with platelet-rich plasma on the symptoms and joint function of patients with knee osteoarthritis in hopes of providing a new ideas for the treatment of patients with early knee osteoarthritis. Methods Forty patients diagnosed with knee osteoarthritis in the orthopedic clinic of Lu'an people' hospital from July 2016 to June 2017 were randomly divided into (intra-articular injection of sodium hyaluronate) and experimental group (intra-articular injection of autologous bone marrow mesenchymal stem cells combined with platelet-rich plasma). The treatment outcomes of the two groups were evaluated at 4, 12, and 24 weeks after treatment based on WOMAC and the VAS. Results The mean WOMAC scores of the two groups were significantly improved compared with those before treatment (all P<0.05), but the mean WOMAC scores of the experimental group at each time point after treatment were better than the control group (all P<0.05). There was no statistical difference in the mean VAS scores between the two groups (all P>0.05). The effective rate of the two groups was not significantly different at 12 weeks after treatment (P>0.05), but the effective rate of the experimental group was significantly better than that of the control group at 24 weeks after treatment (P<0.05). Conclusion Intra-articular injection of autologous bone marrow mesenchymal stem cells combined with platelet-rich plasma can alleviate pain and improve joint function in patients with knee osteoarthritis, and can be used as one of the treatment options for patients with early knee osteoarthritis.