Abstract: cases of the resected margins of the esophagectomy specimens for cancer have been analyzed by flow cytometry(FcM) in an attempt to measure DNA content (DNA Index, DT) and prolifreative index(PI). The results indicated that PI in CD (cut distance, from main tumor margin to cut line)5cm group without residual tumor was higher than that in5cm group and normal group and similars to the group with atypical hyperplasia and the residual tumor group, and 2 aneuploid DNA content were found in5cm group. It is belived that measuring of the resected margins of the esophaus after operation with FCM will aid doctor in determining the objects to be followed-up and assessing patient's prognosis. Another finding was DI and PI in residual tumor were obviously lower than those in the corresponding main tumor (P0. 01).The results showed that residual tumor has a relative lower proliferative activity. The article suggests that residual tumor should be treated immidiately after operation so as to prevent local recrrence.