Nontuberculous mycobacteria are an uncommon cause of peritonitis in patients undergoing continuous ambulatory peritoneal dialysis. We report two cases of peritonitis caused by Mycobacterium abscesses from a single center, which were successfully treated. In endemic areas of tuberculosis, Zeil Neilsen staining should be part of the initial evaluation to allow early detection. Treatment requires removal of Tenckhoff catheter and second-line antibiotics until cultures become negative.