Abstract: The standard spherical lens plays an important role in the Fizeau interferometer. The geometric characteristics and error analysis of standard spherical lens were reviewed. The effect of standard spherical lens on interference illumination optical path and imaging optical path was first analyzed; the R-sinθ geometric characteristics relation model of spherical interference imaging was emphatically introduced and verified with experiments; a new design method of aspheric surface splitting using Q aspheric surface was described, and an two-piece type aspheric standard spherical lens structure was presented; the research results of spherical adjustment error to be measured and phase shift space nonuniformity error for small F-number standard spherical lens were summarized; a wave surface difference algorithm for correcting errors in a spherical interferometer was presented; the effect of retrace error when measuring the spherical surface at the focal position near the standard spherical lens was pointed out; from the conjugation relation angle of object image, the reason of large retrace error of near focal position was explained, and the effect of transmission wave front and slope of standard spherical lens on retrace error was analyzed. The geometric characteristics relation which should be paid attention to when designing the standard spherical lens, the errors which were easy to generate when using the standard spherical lens and the corresponding suppression methods were put forward.