In this paper, some self-fluorescence spectra from gastrocarcinoma and normal tissues were measured, and the flurescence rangge is from 315nm to 600nm. The differences between the fluorescence spectra from gastrocarcinoma tissues and those from normal tissues were found. By these differences, gastrocarcinoma tissues would be distinguished from the normal tissue. The results also give us a new method for dianosing gastrocarcinoma.