Abstract: A 2.5-year-old male British Shorthair cat had been vomiting with difficult defecation and thin stools for 10 days before treatment,. The affected cat was emaciated; its body temperature was 38.5 ℃, and the respiratory rate and pulse were normal. A free hard object could be palpated in the abdomen, and there was no pain when pressing on the abdomen. B-mode ultrasonography revealed a mass 4.41 cm × 3.08 cm in the mid-abdomen. In order to clarify the nature of the tumor and determine the treatment plan, laparotomy was performed on the cat; multiple spherical tumors of different sizes were seen in the mesentery and the tumors were surgically removed; cytology, histopathology and immunohistochemistry were performed respectively. Among them, cytological examination showed cells of various shapes, including scattered spindle cells, and large polygonal cells. Based on this, it was suspected to be neurofibroma and gastrointestinal stromal tumor of stromal origin, or squamous cell carcinoma of epithelial origin. Histopathological examination showed that the tumor cells were arranged in nests; the tumor cells were polygonal or spindle-shaped; the cells were different in size; the nuclei were deeply stained, and a number of pathological nuclei mitotic phases were seen, with obvious atypia; the center of the tumor tissue was accompanied by necrotic foci, with features of low poorly differentiated squamous cell carcinoma. Immunohistochemical staining showed tumor cells cytokeratin（CK） 5/6（+）, DOG1（-）, S-100（-）, SMA（-）, Vimentin（-）, which supported poorly differentiated squamous cell carcinoma. According to the pathological results, postoperative chemotherapy was recommended, but the owner did not cooperate. All indicators returned to normal when discharged after surgery, but close follow-up should be performed.