The invention provides an efficient cement kiln waste heat recovery and power generation system and method, and belongs to the technical field of cement kiln waste heat utilization. The waste heat recovery and power generation system comprises a clinker stepped cooling device, a waste heat recycling device, a turbine power generation device, a cyclic cooling water device and a waste gas treating device. The clinker stepped cooling device comprises a grate cooler and a vertical cooling device. Sensible heat of clinker can be recycled in a stepped mode through the grate cooler and the vertical cooling device. By means of the cooling way, a large quantity of low-temperature waste gas at the tail of a conventional grate cooler is prevented from being directly exhausted, the level of kiln head waste heat resources and the waste heat recovery quantity are improved, and the cement kiln waste heat recovery and power generation efficiency and technical and economical indexes are effectively improved.