The spiral transmission principle results in high sliding speeds and severe frictional wear between the contact surfaces of cylindrical worm drives, presenting a significant challenge that continually constrains their performance enhancements. This paper conducts an in-depth analysis of gear surface contact, obtaining detailed characteristics and conditions within the contact area of cylindrical worm drives. The geometric characteristics of the conjugate tooth surfaces are determined through tooth surface contact analysis, while surface roughness is obtained by fitting with the three-dimensional Weierstrass-Mandelbrot (W-M) function. Building on this, the research develops an elastohydrodynamic lubrication (EHL) numerical model for cylindrical worm drives, examining the specific effects of design and operational parameters on lubrication performance. Numerical analysis are conducted on the variation patterns of maximum oil film pressure, minimum oil film thickness, and friction coefficient under different torque and rotational speed conditions. Through pin-disk lubrication experiments, friction coefficients at multiple points along the contact line are measured, and the experimental results effectively validate the accuracy and reliability of the theoretical model.