Bed sores are a common complication in intensive care unit (ICU) patients who are sedated, ventilated, and/or bedridden for long periods with significant mortality and morbidity. There are many treatment options for treatment of bed sores. Platelet rich plasma (PRP) is considered to be advanced wound therapy. In this study we aimed to evaluate the clinical efficacy of autologous PRP gel in the topical treatment of bed sores. Methods:100 patients with different grades of bed sores were included in this prospective study. Patients were randomly assigned into two equal groups: control group (n=50): Standard treatment was only applied to the wound, and study group (n=50): autologous PRP was directly applied to the wound in addition to the standard treatment. The primary objective of the present study was to follow-up and observe wound healing indices; wound surface area (WSA), healing time, proportion of ulcers healed within trial period (PUHTP), and the pressure ulcer scale for healing (PUSH Tool). Secondary objectives were to assess pain intensity with visual analogue scale (VAS), the frequency of dressing changes, the positive rate of bacterial cultures. Results: The results showed that patients in study group exhibited statistically significant higher ratio of healed area, lower PUSH and VAS scores, and decreased frequency of dressing changes, after one week of treatment and throughout the follow up, in comparison control group. Regarding healing time, it was statistically significant shorter in study group in comparison to control group. In addition, there was statistical significance decrease in WSA and positive rate of bacterial cultures of bed sores in patients of study group after two weeks of treatment in comparison with control group. Conclusion: The administration of topical autologous PRP gel accelerates wound healing with a definite effect in treatment of patients with different grades of bed sores in the ICU. It has proven its clinical efficacy in improvement of wound healing indices, pain intensity, and bacterial cultures.