Based on the space engagement theory and cam theory, an approach of the tooth generation of curve-face gear, concerned the tooth profile equation, tooth characteristics analysis, manufacture and error evaluation is obtained. The tooth surface equation of curve-face gear is obtained and the tooth surface is produced by inserting advanced surface command in SolidWorks combining with the interference analysis. An error evaluation method, based on the extracting points from a series of sections along the tooth length, is put forward. The tooth-flank characteristics, concerned the distribution angle and meshing angle, are analyzed and the interference phenomenon is discussed. Finally, the validity of the theory is demonstrated by the rolling experiment and additive manufacturing.