The　combination　of　sliding/rolling　motion　can　influence　the　degree　of　precision　degradation　of　ball　screw.　Precision　degradation　modeling　and　factors　analysis　can　reveal　the　evolution　law　of　ball　screw　precision.　This　paper　presents　a　precision　degradation　model　for　factors　analysis　influencing　precision　due　to　mixed　sliding-rolling　motion.　The　precision　loss　model　was　verified　through　the　comparison　of　theoretical　models　and　experimental　tests.　The　precision　degradation　due　to　rolling　motion　between　the　ball　and　raceway　accounted　for　29.09%　of　the　screw　precision　loss　due　to　sliding　motion.　Additionally,　the　total　precision　degradation　due　to　rolling　motion　accounted　for　21.03%　of　the　total　sliding　precision　loss　of　the　screw　and　nut,　and　17.38%　of　the　overall　ball　screw　precision　loss　under　mixed　sliding-rolling　motion.　In　addition,　the　effects　of　operating　conditions　and　structural　parameters　on　precision　loss　were　analyzed.　The　sensitivity　coefficients　of　factors　influencing　were　used　to　quantitatively　describe　impact　degree　on　precision　degradation.