A tree transplanting device comprises a moving unit, a hydraulic shovel unit, a moving shovel, a rotating arm, a rotating clamp and an annular rail. The moving unit further comprises a carrying platform, universal wheels, a hand-pushing portion, the carrying platform is used for carrying functional parts, the universal wheels are arranged on the bottom side of the carrying platform and driven by a motor, the hand-pushing portion is arranged on the carrying platform, a handle and a mounting platform of an operating panel are arranged at one end of one side of the hand-pushing portion at an interval, the hydraulic shovel unit is arranged on the carrying platform, a second piston rod of a second hydraulic cylinder of the hydraulic shovel unit is fixed to the moving shovel, the rotating arm is fixedly arranged on the carrying platform through a fixing block, and the annular rail further comprises a rail inner ring and a rail outer ring. The hydraulic shovel unit is utilized to replace manual digging, so that integral separation of root systems of seedlings to be transplanted is realized, adhesion of soil on the root systems is guaranteed, and loss of water and nutrition in the process of transplanting is lowered. In addition, labor intensity is reduced greatly, automation rate of garden tree transplanting is increased, and the tree transplanting device has extremely high popularization and application value.