Objective: To determine the number of HIV-associated non-Hodgkin's lymphoma (NHL) of the gastrointestinal tract (GI) in a population of HIV-infected patients from a distinct geographic region (southern Alberta, Canada), from 1983 to 1995, The type and location of NHL within the GI tract as well it's affect on survival was examined, Patients with GI HIV-associated NHL were compared to patients with extraintestinal HIV-associated NHL. Methods: The Southern Alberta HIV Clinic in Calgary (SAG) serves all of southern Alberta which has an estimated population of one million, SAC provided primary care for 1086 patients from January 1983 to August 1995, Data were obtained by reviewing the clinic's data base and patient's charts, Results: Over a 12-yr period, 13 cases of NHL of the GI tract and 26 cases of extraintestinal NHL were diagnosed in the 1086 HIV-infected patients, HIV-associated GI NHL occurred in individuals of similar age, sex, HIV risk factors, incidence of preceding AIDS-defining illnesses and CD4 count compared to those with extraintestinal NHL, The most common presentations of GI NHL were; abdominal pain (77%), abdominal tenderness (77%), weight loss (77%), and GI bleeding (38%), The most common sites of GI involvement were the large bowel (46%), ileum (39%), and stomach (23%), Those with GI NHL survived longer (1.96 +/- 0.50 yr vs 0.95 +/- 0.20 yr, p < 0.05) and were more likely to respond to therapy (72.7% vs 33.3%, p < 0.03) than those with extraintestinal NHL, Conclusions: This study suggests that; 1) the GI tract is common site of involvement in HIV-associated NHL, 2) HIV-associated GI NHL occurs in similar individuals as HIV-associated extraintestinal NHL, 3) those with HIV-associated GI NHL survive longer and are more likely to respond therapy than those with extraintestinal HIV-associated NHL.