The invention discloses an accurately moving and anti-impact robot leg device. The accurately moving and anti-impact robot leg device comprises a knee joint structure, a shank structure and an ankle joint structure; the knee joint structure comprises a first motor, a first buffering transmission mechanism and a first joint mechanism; a first motor bracket is connected to the lower end of the firstmotor; the first buffering transmission mechanism comprises a first hollow worm and a first buffering spring component; the first joint mechanism comprises a first joint seat and a first worm wheel;the first worm wheel is connected to the interior of the first joint seat through a shaft pin; first connecting supports are arranged on the left and right sides of the first hollow worm; the upper ends of the first connecting supports are fixedly connected with the first motor bracket; the lower ends of the first connecting supports are rotationally connected to the first joint seat through firstsupporting shafts; the shank structure comprises a second motor, a third motor and two leg side plates; and the ankle joint structure is arranged at the lower end of the shank structure. According tothe accurately moving and anti-impact robot leg device, as the novel knee joint structure and the novel ankle joint structure are arranged, the transmission structure is simple and novel, the buffering effect is good, and the creativity is high.