Introduction and importance:A pressure ulcer is a skin and soft tissue injury that commonly occur on bony prominences like the ischium, sacrum, heel, malleolus, and occiput but the knee is not the usual site for pressure ulcers. Here, the authors present a case of a pressure ulcer over an unusual site, the knee.Case presentation:The authors reported a case of a 66-year-old male, last seen 5 days ago by his son, who was found on the floor (with the knee on the ground) and was brought to the hospital. The patient had no history of mobility issue. On initial assessment his vitals were unstable but Glasgow Coma Scale 15/15 and CT head and ECG were unremarkable. On knee examination, there was bilateral grazing and bruising diagnosed as grade 3 and grade 4 pressure sore in the right and left knee, respectively. The pressure ulcer was managed adhering to the principles to remove all pressure, keep the ulcer clean, prevent further injury, and regular dressing by tissue viability nurses. On 17 March 2023, the patient was discharged from the hospital to a care home after his condition improved.Clinical discussion:A comprehensive review of the medical literature found no other reports of pressure sore at knee. A few published articles showed pressure sore as a complication of prone positioning. It is postulated that fall and long-term lie on the knees have developed this pressure ulcer.Conclusion:The Clinicians should be vigilant to check for pressure ulcers especially in all the bony prominences in any patients having an unwitnessed fall.