We report a case of rectosigmoid cancer complicated by pyogenic spondylitis. The patient was a 71-year-old man who had anemia and back pain. Endoscopy revealed a rectosigmoid tumor, confirmed to be well-differentiated adenocarcinoma. Imaging indicated rectosigmoid cancer with pyogenic spondylitis at the L1 vertebra. We performed radical resection (robotic-assisted Hartmann's procedure) after controlling the inflammation caused by pyogenic spondylitis. Colon cancer complicated by pyogenic spondylitis is rare. Here, we describe the mechanisms of this infection and treatment strategies along with a review of the literature.