The invention discloses a tidal flow vortex impeller generator using flows of tides of oceans and rivers as power. The generator is characterized in that an impeller is sleeved in a major arc vortex ferrule with a flow direction rudder, the impeller rotates when blades of the impeller is impacted by tide power, the vortex ferrule arc opening orientation is changed if the flow direction rudder is changed along with the tide flow direction on the vortex ferrule, but the vortex impeller rotation direction is not changed, correspondingly, water flows in the vortex ferrule form vortex flow potential energy due to the rotation of the impeller, and accordingly, the impeller rotation speed is improved, and the impeller rotation is transmitted to generators on the rack surface to generate power. By means of the tidal flow vortex impeller generator, green electricity is provided for fish raft or boat production, living and lighting of the ocean or river aquaculture industry, fishing, transportation and the like. The generator has large practical values.