The invention provides a water absorption tube underwater combined blade vortex-eliminating device, comprising a separating-blocking device; the top end of the separating-blocking device is connected with one end of a connecting shaft in a fastening way, and the other end of the connecting shaft is connected with a fixed guide device in the fastening way; a vortex-eliminating mechanism rotationally connected with the connecting shaft rotatably sleeves the connecting shaft; the center line of the separating-blocking device, the center line of the fixed guide device, the center line of the vortex-eliminating mechanism and the center line of the connecting shaft are mutually superposed. A bottom plate of a water inlet pool is connected with the separating-blocking device in the fastening way, the separating-blocking device is connected with the fixed guide device by means of the connecting shaft, and the vortex-eliminating mechanism rotationally connected with the connecting shaft sleeves the connecting shaft between the fixed guide device and the separating-blocking device, so that vortex and flow separation in a water absorption tube of a water pump can be effectively reduced or eliminated, and a better inflow condition is provided for the water pump.