A 36-year-old man visited our hospital with a complaint of dysphoria of the epigastrium. A torous lesion was observed in the cardia by esophagogastric fluoroscopy. The patient was diagnosed as having submucosal tumor by endoscopic and biopsy examinations, and transgastric excision of the tumor nucleus was undertaken. The tumor was oval-shaped (ca. 5.5cm in a long diameter), white and solid. The histopathological findings indicated benign leiomyoma. The course was favorable two years after operation. Only 28 cases of leiomyoma in the esophagocardiac junction have been reported in Japan. Cases of leiomyoma in the esophagocardiac junction were compared with those in the esophagus and stomach. The most common age of occurrence for leiomyoma in the esophagocardiac junction was relatively young, 30s to 40s, similar to that of lesiomyoma in the esophagus. Chief complaints on admission to hospital also resembled those in esophageal leiomyoma: disturbed deglutition, epigastralgia and subclinical condition. These chief complaints were clearly different from those in gastric leiomyoma, i.e., hemorrhagic symptoms, unidentified clinical epigastric condition and abdominal mass. Leiomyoma in the esophagocardiac junction, esophageal leiomyoma and gastric leiomyoma showed different patterns of tumor development, and preoperative diagnosis is difficult in all cases. Unless specific circumstances (a markedly large tumor suspected of being malignant, full peripheral development of a tumor, or the presence of a serious complication) are present, excision of the tumor nucleus should be carried out as the first choice treatment.