Abstract: Dugesia japonica was radiated by UV-C lamp. The morphological change of planarian was observed, in addition, the effect of the radiation on activities of lactic dehydrogenase (LDH), Na+-K+-ATPase, Ca2+-Mg2+-ATPase, superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-PX) was studied. The result indicated that UV-C radiation caused obvious damage of the planarian, and the livability of the planarian was related negatively to radiation time. In addition, with the prolonging of UV-C radiation time, the activity of LDH has the decreasing trend; the activity of Na+-K+-ATPase has the increasing trend while the activity of Ca2+-Mg2+-ATPase has the decreasing trend; the activity of SOD increases obviously; the activity of CAT has the upward trend and the activity of GSH-PX fluctuates, but the total trend is increasing. Based on the damage of the planarian from UV-C radiation and the effect of the radiation on the activities of six enzymes, Dugesia japonica should be very sensitive to UV-C radiation and has application prospects and great potential value in UV radiation detection and screening of the anti-ultraviolet radiation protectants.