In the development of new photosensitizers for cancer therapy, increasing the capacity of intracellular reactive oxygen species (ROS) production is an important strategy. In this paper, artesunate as a ROS generation group was regioselectively introduced to the chlorin e 6 scaffold to obtain four conjugates of chlorin e 6 and artesunate. By irradiation with 440 nm, 630 nm and 660 nm of light source the four conjugates exhibited significantly improved phototoxicity against HepG2 cells compared with chlorin e 6 and artesunate. Irradiation with 440 nm or 660 nm light source gave higher phototoxicity as well as intracellular ROS level.