The invention discloses a high-power transmission power cable. The high-power transmission power cable sequentially comprises a combined water passing pipe layer, a fine copper wire harness layer, an isolating layer and a rubber layer from inside to outside, wherein the fine copper wire harness layer is arranged outside the combined water passing pipe layer, the isolating layer is arranged outside the fine copper wire harness layer in winding and coating modes, and the rubber layer is arranged on the outermost layer of the high-power transmission power cable in squeezing and coating modes. Control pairs are further arranged inside the fine copper wire harness layer, and the control pairs are tightly attached to the combined water passing pipe layer. The combined water passing pipe layer is composed of a cooling water pipe and a cold pipe closing layer which is arranged outside the cooling water pipe in a coating mode. The high-power transmission power cable is in the state of external natural cooling and center forced cooling in the working process, the control pairs are tightly attached to the cooling water pipe, insulating strength can be better maintained, thermal ageing is slowed down, and the stress is small when the cable is bent.