In order to obtain a 1080 nm miniaturization, high power, continuous fiber laser, a 915 nm semiconductor laser diode (LD) is used as the pump source, and the resonant cavity is composed of two fiber gratings. Combining with beam combiner, stripping mold, collimator and other optical devices, an all fiber laser system is constructed using 12 m Yb-doped double cladding fiber as the gain medium. When the pump power is up to 118 W, a continuous and stable laser output with a power of 80 W and an optical conversion efficiency of 68% is obtained experimentally. The laser system is assembled into a self-designed compact cuboid aluminum housing. The total weight of fiber laser is less than 1.8 kg, and the volume is 200 mm×160 mm×40 mm. It can work stably in environment ranging from -40 °C to 50 °C.