Accessory transmission gear box of gas turbine

The invention discloses a gas turbine accessory transmission gear box and relates to the technical field of gear transmission. The problem that an existing gearbox cannot drive other fuel accessories to provide lubricating oil for equipment when a gas turbine casing is started is solved. The coupling is provided with a slotted bushing, a first half coupling, a second half coupling, a slotted shaft, a driving half coupling, a driven half coupling, a transition bevel gear, a casing bevel gear and an accessory bevel gear, the other end of the first half coupling is connected with one end of the second half coupling, and the other end of the second half coupling is fixedly connected with one end of the slotted shaft; one end of the driving half coupling is fixedly connected to the slotting shaft in a sleeved mode, the other end of the driving half coupling is connected with one end of the driven half coupling, an outer ring straight gear is arranged on the outer circumferential side wall of the driven half coupli