Pneumatosis intestinalis (PI) occurs when gastrointestinal (GI) wall disruption, increased wall permeability or necrosis leads to wall infiltration by gas. It is associated with a spectrum of causal factors, including GI disease in allogeneic blood and marrow transplant patients. Traditionally, PI has been managed surgically with high morbidity and mortality. We describe our experience managing allogeneic blood and marrow transplant patients with PI. From January 1998 to May 2008, 320 patients underwent allogeneic blood and marrow transplant of whom 10 were identified with PI. PI diagnosis was established by computed tomography scan (n=7), plain film (n=2) or colonoscopy (n=1). A total of 9 of 10 patients had ongoing GI GvHD or received recent treatment for GI GvHD. Before April 2002, two patients underwent subtotal colectomy with ileostomy (n=1) and sigmoid colectomy with colostomy (n=1). One patient was managed with bowel rest and total parental nutrition (TPN) only. These three patients died 0.4, 1.1 and 3.9 years after PI diagnosis owing to GI GvHD (n=2) and surgical complications (n=1). Seven patients, diagnosed after September 2006, were treated with GI rest, TPN and antibiotics. PI treated with GI rest, TPN and antibiotics will resolve without surgical intervention. AlloBMT-associated PI is often a non-critical finding that does not represent true GI tract ischemia and/or GI tract perforation.