The invention relates to a fluid pipeline electricity generating device. A front valve (2) and a rear valve (3) are respectively arranged on the front and rear parts of the fluid pipeline (1) of the invention, a closed turbine electricity generating pipeline (4) is connected at the front part of the front valve and the front part of the rear valve of the fluid pipeline (1), a turbine (5) is installed in the turbine electricity generating pipeline, and the turbine is connected with an electric generator (6) outside the turbine electricity generating pipeline; the connection method is that a clutch coupling device (9), a gear transmission case (10), a coupling device (11) and an electric generator are connected on the turbine axle in sequence; the invention also comprises a battery, an electric generator controller (13) and a cutting-in controller; the hydraulic pressure of the fluid conveyed through the existing pipeline is fully utilized by the invention, the device is connected to generate electricity under the condition the original hydraulic pressure is not increased, the generated electricity is directed cut in the regional power grid, and the invention has the remarkable advantages that the manufacture cost is low, the invention is easy to manage and maintain, the voltage of the generated electricity is steady and reliable, as well as the invention can be used to generate electricity constantly.