Fecal stones and fecal masses in the appendix and the normal feces were examined by spectrometric analysis, and the following results were obtained. 1. The component elements of the fecal stone or fecal mass were Ca., Mg., P., Al., Si, Mn, Na, Cu, Fe, K, Ti and B, among which Ca, Mg and P were always found. 2. No difference was observed in the component elements between the fecal stone and the fecal mass. 3. The component elements of the normal feces were Ca, Mg, P, Al, Si, Mn, Na, Cu and K, among them Ca, Mg, Si, P, Cu and Na were always found. 4. The fecal stone contained more P, Si and Mn and less Al and K than the normal feces. 5. The increase of Ti, Fe and B and the changes of P, Si, Mn, Al and K in the fecal stone are considered to be due to the inflammatory process, and this fact was observed even inside of the stone. 6. A considerable quantitative difference of the component elements except Ca, Mg and P was seen between the two stones in the same appendix.