The invention provides a technology used by a cascade hydropower station to continuously generate power twice, and the technology comprises a pressure pipe used for power generating, wake recycling and water drawing, a hydropower station outside a dam, a generator workshop outside the dam, a hydro-generator, a wake discharging pipe, a discharging buffer pool, a backwater trench, etc. The pressure pipe used for power generating, wake recycling and water drawing recycles the power generating abandoned water wake of the hydropower station, so as to enable the power generating abandoned water wake to form a secondary generating head outside the dam, and drive the hydro-generator of the hydropower station outside the dam to output power for generating, thereby realizing the hydropower station continuous cascade power generating outside the dam. The technology used by the cascade hydropower station to continuously generate power twice is realized outside the dam of the hydropower station, thereby being not limited by the dam foundation conditions, and having technical economic superiorities and development potentialities such as large technology flexibility, strong operability, short construction period, wide application scope, obvious economic benefit, etc.