Several cases of photodynamic therapy (PDT) for the curative treatment of early gastric cancer have recently been reported. However, PDT has been performed in only limited cases because it is impossible to determine the pathologic subtype or stage of the malignant lesion after the procedure. Nevertheless, PDT combined with endoscopic submucosal dissection (ESD) is expected to enhance the accuracy of the pathologic assessment and enable more effective, safe treatment for early gastric cancer. Furthermore, PDT may exert a complementary and synergetic effect on ESD for the atypical forms of early gastric cancer. From this background, we report here on a case of early gastric cancer that mimicked submucosal tumor, and this was removed by ESD, and then this was followed by adjuvant PDT. The patient had a high risk for operation due to his old age and comorbidity. After the procedure, he achieved complete remission and he is currently under follow up: he is without recurrence of tumor one year after ESD.