Summary.Two different techniques of human sperm motion analysis were compared. In 25 ejaculates, diluted to an appropriate concentration, the sperm motion index called “specific progressive motility” (SPM) was assessed by a modified conventional method. The same sperm preparations were also analysed by the CellSoft® system for computer assisted sperm analysis (CASA). The SPM‐value was found to correspond mainly to the variables motility and curvilinear velocity presented by CASA (multipler= 0.92,P<0.001). Linearity of sperm progression, lateral head displacement, and beat cross frequency did not significantly contribute to the relationship between SPM and CASA. For comparative studies between SPM and CASA the logarithmic values of SPM are recom