We present the case of a patient under study due to ascites in which a mass located on the gastric wall was observed during ultrasonography. Further studies (upper endoscopy and computed tomography) confirmed this finding. After an ultrasound-guided percutaneous biopsy, diagnosis of gastric schwannoma was made as intense S-100 expression was found. Surgery was rejected due to the bad clinical situation of the patient and because the mass was an asymptomatic benign tumor.