Abstract: To study the influence of C6o monoadducts on the growth of Hela cells, two C6o monoadducts: ethyl caboxylic C6o, (C1) and glycinate derivative of C6o, (C2) were prepared; C6o,C1 and C2 were introduced into water with PVP and then their effects on the growth of HeLa cells were studied by MTT assay under different irradiation conditions. Both PVP solutions of C6o and C1 showed no obvious effect on the growth of HeLa cells under any of three irradiation conditions (the power of the light was o W, 1oo W, 3oo W,respectively), while C2 can remarkably inhibit HeLa cells growth when the light power is 3oo W. The effects of C6o derivatives on the cells growth were related to the side chain structure, and were also dependent on the power of the light irradiation.