Background: Disuse Syndrome is defined as a significantly reduced functional state due to acute disease or surgery. Despite the many advantages to robot rehabilitation, there have been no reported cases of robot rehabilitation being applied to patients with disuse syndrome. Objectives: To investigated report cases of robot rehabilitation in patients diagnosed with disuse syndrome after severe COVID-19 infection. Design: Case report. Methods: The subject of this study was an 81-year-old male who was 161 cm tall and weighed 55.3 kg. At the time of admission to the hospital, the patient had a manual muscle testing (MMT) score of 36 points and a modified barthel index (MBI) score of 7 points. Additionally, the patient had a fall risk assessment score of 10 and a visual analogue scale of 6 for lower back pain. The patient's MMT, trunk impairment scale (TIS), and MBI were followed up. The patient received acute rehabilitation treatment for 4 weeks, followed by additional robotic rehabilitation. For 4 weeks, a standing tilt robot and a wearable robot were applied for 2 weeks each. Results: After 4 weeks of intervention, MMT, TIS, and MBI were improved in the patients. MMT improved from 36 points to 41 points. TIS improved from 0 to 13 points. MBI improved from 7 points to 29 points. Conclusion: There is a need to pay more attention to the rehabilitation of patients with disuse syndrome in recovery rehabilitation hospitals. It is speculated that robot-assisted rehabilitation can be applied to patients with disuse syndrome.