Diabetes mellitus is a major risk factor for urinary tract infection (UTI); emphysematous pyelonephritis (EP), a complication of UTIs, often occurs in patients with underlying, poorly controlled diabetes mellitus. We report the case of an 87-year-old woman with EP in type 2 diabetes mellitus who developed pneumatosis cystoides intestinalis (PCI) with portal venous gas. PCI is a radiographic finding, which is found in a linear or cystic form of gas in the submucosa or subserosa of the bowel wall. PCI has two common presentations. Primary PCI is a benign idiopathic condition. Secondary PCI is associated with a wide variety of gastrointestinal and nongastrointestinal diseases. PCI with portal venous gas in particular is associated with ischemic gastrointestinal disease. Initial pre-enhanced abdominopelvic computed tomography showed EP in the right kidney without PCI. Newly occurring PCI and hepatic portal venous gas were found in the right ascending colon after EP improved. This is a rare case of PCI accompanied by emphysematous pyelonephritis in type 2 diabetes mellitus. The patient's general condition improved with intravenous antibiotics and fluid therapy without a surgical approach. However, she was discharged without further treatment because the family refused any further evaluations and treatments. (