Abstract: In order to study the actual cutting trajectory of surface miner，the basic operating type of surface miner was summarized，and the influence factors of the cutting trajectory were analyzed.By integrating the component of velocity on x and y direction，the trajectory calculation model was obtained in both clockwise and counterclockwise cutting mode，and the functional relationship between the cutting trajectory length L and horizontal velocity v，mining depth h，roll radius R and rotational speed ω was established.By studying the surfer miner of T1255，the relationship between length and difference of the two kinds of cutting trajectory and h，R and ω.The results show that the cutting trajectory of clockwise type is longer than counterclockwise，and the largest difference of power consumption is 6.83 kN·m.The two kinds of cutting trajectory increase with h increasing when rotational speed is fixed.While rotational speed is variable，cutting trajectory of clockwise increases firstly with the mining depth increasing，and reaches maximum when h= 0.5 m，then decreases with the mining depth increase.The counterclockwise cutting trajectory changes along with the mining depth increasing，and reaches the maximum at the largest mining depth.

Key words: Surface miner, Cutting trajectory, Cutting ways, Selected mining depth