Aimed at the problem of internal flow field and leakage of compressor labyrinth seal,optimization research was carried out on the cylinder side sealing teeth in the double-sided labyrinth seal structure.Three types of cylinder side sealing tooth structures,such as triangular,rectangular,and cycloidal were designed,different geometric ratios of tooth height,tooth width,and sealing tooth clearance between the cylinder side and piston side sealing teeth were selected from 1∶2 to 1∶6,and the double-sided sealing models with different sealing tooth structures were established.The sealing performance of the double-sided sealing models was analyzed by CFD dynamic mesh transient simulation,and was compared with that of the single-sided sealing tooth structure model.The results show that the leakage of the double-sided sealing tooth structures reduced by 25.8% to 56.0% compared with the single-sided sealing tooth structure.The sealing performance of cylinder side sealing teeth with three different shapes is in descending order:triangular,rectangular,and cycloidal.Among the five different geometric ratios of cylinder side sealing tooth models,the sealing performance is arranged from strong to weak as 1∶4,1∶5,1∶2,1∶6,and 1∶3.The sealing performance of the triangular cylinder side sealing tooth structure that the geometric ratio of the sealing teeth between cylinder side and piston side is 1∶4 is the best,and the leakage rate is reduced by 56% compared to the single-sided sealing tooth structure.