To explore the transmission efficiency of single-roller enveloping face worm drive,taking transmission efficiency as research subject,the mathematical model of the transmission pair was established based on the meshing theory of single-roller enveloping face worm drive.The instantaneous transmission efficiency and average transmission efficiency of the transmission pair were calculated.The influence of the main parameters of the transmission pair on the average transmission efficiency of the transmission pair was analyzed.Using MATLAB for optimization calculations,high transmission efficiency parameters were obtained.The research results show that the average transmission efficiency of the transmission pair is negatively correlated with friction coefficient,throat coefficient,roller radius,and worm gear tooth number,and positively correlated with center distance.Among them,the friction coefficient has the most significant impact on the average transmission efficiency of the transmission pair,followed by the number of worm gear teeth,and the center distance has the least impact.