For the preparation of the HCl-pepsin solution generally used in artificial digestion assay of protein, it is advantageous to know the distribution of the secretory cells of three types in the gastric mucosa of swine. They are the zymogenic, parietal, and mucous neck cells secreting pepsinogen, hydrochloric acid, and mucus, respectively. <br>In the present paper, the distribution of these cells in the gastric mucosa, mainly in the fundus, is described. <br>1) Sixteen pieces of mucosa about one cm square each collected from the fundus of the stomach, were treated, fixed, and stained by a specific method described below. Two more specimens of the same size were harvested, one from the pyloric and the other from the cardiac gland region, and manipulated in the same way. <br>Each specimen was fixed for 4 days in a solution consisting of one part of 35% neutral formalin and three parts of saturated corrosive sublimate solution, followed by rinsing in running water for 24 hours. After the treatment with Lugol's solution and rinsing, it was dehydrated, imbedded in paraffin, and sectioned 5μthick.<br>The sections were stained with Schiff's reagent (PAS) and aurantia. <br>2) Nuclei of the cells were counted under the microscope of 400-time magnification by the aid of a cross micrometer with 25 one-square-mm meshes. <br>In the cranio-caudal observation at, the fundus, the zymogenic cells were distributed in the base, body, and neck of the gland in the decreasing order, but the parietal cells in the neck, body, and base, in the decreasing order. The mucous neck cells were contained almost equally in those areas. <br>In the transverse observation, the zymogenic cells were contained in a larger number at a portion of the fundic gland region close to the cardiac gland region. On the contrary, the mucous neck cells were found mostly at another portion of the fundic gland region near the pyloric gland region. The parietal cells were distributed almost equally. <br>In conclusion, the zymogenic cells were contained in the largest number in the base of the glands in a portion of the fundic gland region near the cardiac gland region. Such portion of the region may be called the pepsinogen zone. <br>3) In the microscopic observation, no zymogenic nor mucous neck cells were found in the pyloric and cardiac mucosa, while some portions of the cardiac mucosa were stained yellow, where a few cells similar to the parietal cells, were observed. <br>The cells of the cardiac and pyloric gland regions were stained intensely red, especially remarkable in those of the latter region, which was very similar to the mucous neck cells in morphology and staining features. Consequently, from these observations the cells of the pyloric gland region may be a sort of mucus-secreting cells similar to the mucous neck cells.