The invention relates to a hindered-settling separation method for the light substance of hydraulic concrete coarse aggregate, which pertains to a separation method of hydraulic concrete coarse aggregate in hydropower engineering. The method comprises: 1. separation equipment is selected, a slurry pump is operated to fill a flume with water; and a bucket-typed elevator is operated to run smoothly; a belt conveyer is operated, and coarse aggregate containing light substance is fed into the flume by a feeding inlet; a diverter valve and a turbulent board are adjusted according to the feeding quantity and the density of the light substance. The method of the invention has the advantages that the light substance with different densities can be removed. Under the situation of proper inverted water flow and turbulent condition, the separation efficiency can reach 100 percent, and the addition of the cost of the coarse aggregate is respectively reduced by 41 percent compared with the other two techniques.