To provide a linear power generation device for converting pressure fluctuation of exhaust air generated in a pulse shape on the output side of a device such as an air compressor or a vacuum pump to power.

A linear power generator 30 is installed at a branch tube installed in an exhaust tube of the device to generate power by making pressure fluctuation of exhaust air directly collide with a power reception plate 1 of the power generator. The linear power generator 30 generates power by making exhaust air generated in a pulse shape of the device collide with the power reception plate 1 connected to a piston rod of the linear power generator 30 while separating the linear power generator 30 from the exhaust tube by using the following methods: (1) the linear power generator 30 is installed inside a housing installed in a receiver tank 26; (2) the linear power generator 30 is installed outside the receiver tank 26 so as to keep pressure outside the receiver tank 26 different from that of the inside; and (3) the linear power generator 30 is installed inside the receiver tank 26 while keeping pressure inside the linear power generator 30 different from that of the outside by using a bellows 23.