An eight-year-old, female intact, boa constrictor (Boa constrictor) was presented for a 1.5- month history of wheezing, open-mouth breathing, and hyperextension of the neck. Radiographs, ultrasound (US), computed tomography (CT), and tracheal endoscopy revealed an intra- and extraluminal tracheal mass occluding approximately 95% of the tracheal lumen. Complete blood count and biochemistry panel were unremarkable, except for a moderate elevation of the hematocrit. A caudal saccular lung cannulation was placed as an emergency procedure because of worsening respiratory distress. Resection of 22 tracheal rings, inclusive of the mass, followed by anastomosis of the trachea was performed. Histopathology, immunohistochemistry, and electronic microscopy (EM) were consistent with a tracheal round cell neoplasia. Eleven months after the initial surgery, the snake presented for a caudal coelomic mass associated with constipation. Radiographs, US and CT findings were consistent with an infiltrating circumferential colonic mass, which was surgically resected. Histopathology and EM confirmed a round cell tumor that was morphologically identical to the previous tracheal tumor. In addition, cytoplasmic eosinophilic inclusions, consistent with subclinical Inclusion Body Disease (IBD), were noticed in the colonic mass. Eleven weeks after the second surgery, recurrence of the mass was observed in the colonic surgical area. A single L-asparaginase injection was attempted as a palliative treatment, and was unsuccessful. As the snake's condition declined, euthanasia was elected. Necropsy confirmed multiple malignant T-cell lymphoma in the esophagus, stomach, and colon. This is the first report of a tracheal and digestive tract malignant T-cell lymphoma in a boa. Surgical management of this case provided a palliative treatment for a life-threatening disease and a survival time of 14 months from initial presentation. Also, this is the third case report of a lymphoma in a boa with a concurrent IBD.