The utility model discloses a fishway with invariable import velocity of flow, include the fishway main part that extends to the upper reaches in the water from low reaches and set up the shaft in the water low reaches, the opening that the fishway main part is located low reaches forms the fishway import, and the opening that is located the upper reaches forms the fishway exit, the shaft with the one end that the fishway main part is located low reaches is met and will the fishway import is surrounded, the shaft inside with form a waters space between the fishway import, be equipped with at least one intercommunication on the shaft the waters space with the shaft is outside enters the fish hole. The utility model discloses a fishway with invariable import velocity of flow through setting up the shaft in the fishway import, makes between its and the shaft to form a waters space, and the outside low reaches water water level of water level and shaft is with rising with falling, the stability that downriver keeps the fishway import ope of waters velocity of flow and flow state under the undulant circumstances of water level, and simple and practical can help the fish to find the fishway to import.