Purpose. To improve the cure of knee osteoarthirtis using a combination of arthroscopic laser surgery and intraosseous infiltration of autologous platelet-rich plasma (PRP). Material and methods. 32 patients (18 men and 14 women) with osteoarthrosis (OA) of the knee joint, degree II–III (by Kellgren–Lawrence classification), participated in the study. By MRI findings, all patients had meniscus and cartilage damage. The arthroscopic intervention was done with laser device «LSP IRE Polyus», wavelength 0.97 mkm. In addition to the arthroscopy, patients were made extra-articular intraosseous infiltration of autologous platelet-rich plasma topically into the altered subchondral bone under the control of an electronic optical transducer (OEC Fluorostar 7900 COMPACT 2). The evaluation of treatment efficacy was made using WOMAC and KOOS knee function assessment scales, as well as VAS scale (pain intensity) before surgery and 1 and 3 months after the treatment beginning. Results. In 3 months, WOMAC scale showed the improved knee joint function by 25.38 points, KOOS scale – by 37.4 points and VAS scale – by 35 points (p < 0.01). Thus, the performed curative technique increased the support capacity, range of motion in the knee joint, less pain – all these contributed to the achievement of prolonged effect.