A tree trimming apparatus includes a movable carrier, a shredder device, a transmission hose, and a support stand. The movable carrier has a container. The shredder device includes a housing, a plurality of cutters, and a motor. The housing has a through hole. The cutters are rotatably positioned in the housing. The motor is located on the housing and is connected to the cutters. The transmission hose has a first end portion and a second end portion. The first end portion is connected to the through hole, and the second end portion is aligned with the container. The support stand is connected between the movable carrier and the shredder device. When the cutters contact a branch, the branch is cut and enters the housing, and falls into the container through the through hole and the transmission hose.
