We report a case of well leg compartment syndrome (WLCS) in both legs after robot-assisted laparoscopic prostatectomy (RALP). A 65-year-old man underwent surgery for prostate cancer. He was placed in the lithotomy position and both his legs were protected with elastic stockings and intermittent pneumatic com- pression to prevent deep vein thrombosis during sur- gery. After surgery, he complained of pain in both calves. Movement and sensory disorder along with swelling were found in both legs. Computed tomogra- phy of the legs showed damage to the soleus and gas- trocnemius muscles of both legs. The creatinine phos- phokinase level had increased to 10,560 IU · l⁻¹. The patient was diagnosed with WLCS in both legs and underwent conservative treatment. Symptoms in both legs started to improve from the next day. The right leg swelling receded within 10 days, while the left leg swelling receded 67 days after surgery. WLCS in the legs after RALP is a rare but severe complication requiring early diagnosis and intervention. To prevent WLCS, it is important that we recognize this disease as a potential complication after RALP.