Abstract: The calculation for the caster angle of cardan shaft in the skew rolling mill is more complicated than that in general rolling mill. Furthermore the affected factors are comparatively greater for the angle of cardan shaft in the skew rolling mill. In order to prevent the slide block of cardan shaft from wearing seriously, the cardan shaft in the skew rolling mill must be rational designed. This article presents the calculating formula of the caster angle of cardan shaft and discusses principles for designing rational cardan shaft in the skew rolling mill.