The invention relates to a branch cutting and sawing device close to a transmission line in an electric system.The branch cutting and sawing device is characterized by comprising a supporting rod and the like, the cross section of the supporting rod is in a hollow chord secant annular shape, a bearing, a hollow plate and an elastic element are arranged on a bearing pedestal, a cutting arm comprises a rear plate, a bending section, a front plate, a clamping block and a chain saw groove, a chain saw comprises a driven gear, a chain saw body and a chain wheel, a cutting arm drive device comprises a connecting rod, a slide block, a first slide way, a pull rod and a second slide way, a chain saw transmitting device comprises a transmitting chain, a driving gear and a power device, and a broken branch holding device comprises a first clamping plate and a second clamping plate.The use method includes the steps of wearing and fixing, cutting arm position adjusting, cutting, holding and branch taking.The chain saw can be driven by the power device to cut and clamp branches in high places; the device can be hung on an operator through a belt and a protection plate.