A water-cooling heat dissipator mounted on an electronic heat-generating element includes a water-cooling head member and at least one heat pipe. The water-cooling head member includes a first cover and a second cover connected to the first cover. Both ends of the first cover and the second cover are formed with a receiving portion corresponding to each other, respectively. The receiving portions are adapted to be connected to the conduit connectors. A channel portion is formed between the first cover and the second cover for receiving one end of the heat pipe. With the above arrangement, the present invention can perform the heat dissipations of different heat-generating elements simultaneously to make the heat-generating elements operate under acceptable working temperatures. Further, the present invention can be widely used in the heat dissipation of compact electronic products.