Multiple primary malignant neoplasms (MPMNs) are rarely reported and it is important to give early diagnosis and proper therapy for these patients. Here reported a case of 62-year-old man with concomitant three early stage cancer lesions in upper gastrointestinal tract, all of which were detected by endoscopy. The first one was an llc-type lesion at angular part of stomach under endoscopy, which was histologically confirmed to be a mucosal well-differentiated adenocarcinoma.The patient underwent a standard radical gastrectomy for the lesion after the failure of endoscopic treatment. The other two neoplasms were observed during follow-up and were indicated as early stage lesions by synthesizing information from endoscopy, endoscopic ultrasonography, computed tomography and biopsy. One displayed as a hyperemic patch (3cm×4 cm in size) located at the part of esophagus 27 cm away from the incisor teeth and was proved to be moderately differentiated squamous cancer by histopathological examination. The other was an llc-type lesion (3.0 cm×3.5 cm in size) located at the part of esophagus 36 cm away from the incisor teeth, and the biopsy result showed a poorly differentiated squamous carcinoma. Both the two lesions were treated with radical radiation because the patient refused surgery management. No recurrence of former lesions or occurrence of novel lesions were observed during post-treatment follow-up, suggesting radical radiation might be effective for this patient.