To improve the cutting depth of chemical vapor deposition （CVD） diamond， the effects of laser power， focus position， repetitive frequency， scanning speed， and transverse mode on the width of cutting seam， cutting depth， and roughness of CVD diamond was used to achieve a novel high repetition rate laser with acousto-optic modulation. The results show that the cutting depth and width of upper kerf increased with the increase in laser power； the maximum cutting depth was obtained when the focus was moved down along with cutting depth； the cutting depth decreased and the width of upper kerf increased with an increase in repetition frequency； with the increase in cutting speed， the surface roughness decreased slowly and increased significantly subsequently； the width of upper kerf increased with the increase in the number of laser modes. The best result is obtained with a unidirectional cutting depth of 7.2 mm， surface roughness of 0.804 μm， and kerf’s width of 350 μm， while the laser power is 12 W， repetition frequency is 6 kHz， cutting speed is 1 500 mm/min， and the focus position is located on the concave surface. Hence， a large cutting depth of CVD diamond with low surface roughness is achieved.