A review of 167 cases of esophageal carcinoma without preoperative treatment revealed 24 (14.4%) to have intramural metastasis (IM) within the esophagus. Among the clinicopathologic factors, the length of the lesions (P < 0.01), lymph node metastasis (P < 0.001), and the depth of the invasion of the tumor (P < 0.0001) were found to be statistically significant different factors between the two groups of patients both with and without intramural metastasis. The survival curve for patients with IM was significantly lower than that for patients without IM (P < 0.0001). A univariate analysis revealed that the depth of invasion, lymph node metastasis, IM (P < 0.0001), and the length of the lesion (P < 0.001) all had a significant correlation with the prognosis. Moreover, in a multivariate analysis, the depth of the invasion (< 0.001), length of the lesion (0.001), and IM (0.049) were all determined to be significant prognostic factors. Therefore, IM is considered to be one of the independent significant prognostic factors for predicting a poor prognosis in esophageal cancer.