This paper systematically reviews the research progress on ecological compensation for water diversion. Compared with the ecological compensation within the basin, the ecological compensation for inter-basin water diversion has different characteristics, including the impact of water diversion project on water source basin and water receiving regions, compensation relationship between upstream and downstream areas of water source basin and water receiving regions, and the loss in the lower reaches of the water source basin. The calculation methods for ecological compensation standard for cross basin water diversion evolve from the methods for inner basin compensation, including methods based on cost and opportunity loss, willingness to pay, resource value loss, and ecological footprint. The compensation volume was distributed according to the water quantity, benefits received by different regions, and their willingness to pay. Because of the complicity in the impact of water diversion on the water source basin and receiving regions, as well as the networked water diversion structure, key technologies for further studies were proposed. The first is the quantitative assessment of impact of water diversion on the water source basin and receiving regions. The second is the holistic estimation of cost and loss in the water source basin caused by water diversion. The third is the evaluation of economic, social, and ecological benefits brought to the water receiving regions. The fourth is construction of compensation relationships and calculation models for compensation standard, based on the estimation of cost, opportunity loss, and benefits. The last is the principle and calculation technology of compensation standard available for the complex compensation relationships under the networked water diversion structure.