Based　on　the　thought　of　separating　non-functional　properties　from　functional　properties　of　Web　Service,　a　composition　Web　Service　selection　model　based　on　non-functional　properties　is　put　forward,　in　which　executing　sequence　of　the　composition　service　has　been　given.　On　account　of　both　incommensurability　and　confliction　among　non-functional　properties,　a　new　mixed　intelligent　optimization　algorithm　making　use　of　both　the　advantage　of　Maximum　Entropy　Method　and　Social　Cognitive　Optimization　is　introduced　to　achieve　the　optimal　result　for　the　service　selection　model.　Finally,　numerical　experiments　are　given,　which　demonstrate　that　non-functional　requirements　can　be　comprehensive　considered　for　achieving　the　global　automatic　service　selection.