Fifty six SD rats were randomly divided into the normal control group and the operation group. The operating group was subdivided into six groups on the basis of killing time (the 12th h, the first day, 3rd day, first week, 2nd week and 4th week) after vagotomy (VG). The pancreatic tissues were taken for HE and Feulgen staining. The DNA content of pancreatic exocrine cells was determined by a domestically fabricated computer image analyzing system. In the control group, on the first day or in the first week after VG, the pancreatic samples were taken for transmission electron microscopic examination. The DNA content of pancreatic exocrinal cells was decreased from 1 to 3 days after VG. The secretion was found to be in inhibitory state and One week later, it gradually restored. The results indicated that the proliferation and the function of the SD rat’s pancreatic exocrinal cells were prohibited at initial stage after VG, which might be concerned, at least in part, with dominance and nutrition of vagus. The operating group was subdivided into six groups on the basis of killing time (the 12th h, the first day, 3rd day, first week, 2nd week and 4th The pancreatic tissues were taken for HE and Feulgen staining. The DNA content of pancreatic exocrine cells was determined by a domestically fabricated computer image analyzing system. In the control group, on the first day or in the first The after VG, the pancreatic samples were taken for transmission electron microscopic examination. The DNA content of pancreatic exocrinal cells was decreased from 1 to 3 days after VG. The secretion was found to be in inhibitory state and one week later, it gradually restored. The results indicated that the proliferation and the function of the SD rat’s pancreatic exocrinal cells were prohibited at initial stage after VG, which might be concerned, at least in part, with dominance and nutrition of vagus.