In　mixed　traffic,　non-motorized　block　interference　can　cause　the　delay　of　road　traffic　flow,　which　has　not　been　studied　completely　because　of　lacking　definite　mathematical　model　and　calculation　method.　Aiming　at　two-lane　road,　this　paper　establishes　a　model　to　analyze　the　delay　of　road　traffic　caused　by　non-motorized　for　mixed　traffic　quantitatively.　To　some　extent,　this　model　can　be　used　to　evaluate　service　level　of　road　and　determine　reasonable　road　resistance　function.