OBJECTIVE: To evaluate the association between chromatin structure and sperm motility. DESIGN: Cross-sectional prospective study. SETTING: Scanian Andrology Centre, Malmö, Sweden; ENEA Casaccia, Rome, Italy; and Department of Occupational Medicine, Aarhus University, Aarhus, Denmark. PATIENT(S): One hundred seventy-one males from Danish first pregnancy planner couples (group 1) and 278 Swedish military conscripts (group 2). MAIN OUTCOME MEASURE(S): Sperm chromatin structure assay (SCSA) parameters, DNA fragmentation index (DFI), high DNA stainable (HDS), and sperm motility, which was evaluated manually and by use of computer-aided sperm analysis (CASA). RESULT(S): A statistically significant negative correlation between DFI and the CASA percentage of motile sperms (group 1: r = -0.53; group 2: r = -0.38) was found. For the manual motility assessment, the correlation coefficients were slightly lower. Furthermore, HDS correlated negatively with CASA sperm motility (group 1: r = -0.39; group 2: r = -0.36) and percentage of World Health Organization category A motile sperm. In multiple linear regression analysis, concentration and SCSA parameters, but not the time of abstinence, were statistically significant predictors of sperm motility. CONCLUSION(S): There is a moderate correlation between sperm motility and SCSA parameters. The study supports the assumption that both SCSA and motility can be relatively independent predictors of male fertility.