PROBLEM TO BE SOLVED: To provide a hydraulic power generator capable of being easily installed in a water channel free from a waterfall work with a simple constitution, and generating electric power by effectively utilizing energy of water flowing in the water channel.SOLUTION: A hydraulic power generator includes a runner 20 disposed in a water channel 12 in a state of blocking a flow channel and rotated by receiving water flow, and a power generator 50 generating electric power in conjunction with the runner 20. Further it includes a runner holding frame 36 holding the runner 20, and a water level adjustment cover 54 disposed while covering the runner 20, guiding the water flow in the water channel 12 to flow to a blade 42 below the runner 20, and adjusting a water level at an upstream side. The water level adjustment cover 54 is positioned almost over the whole width of the water channel 12 in a state that its position in the water depth direction can be adjusted. The water level adjustment cover 54 is swu
