Maintenance　of　concrete　structure　has　become　a　hot　topic　at　present.　In　order　to　develop　high　performance　materials　for　repair　of　concrete　structure,　two　species　of　polymer　latex　were　selected　to　modify　cement　mortar.　Experiments　of　compressive　strength,　flexural　strength,　adhesive　bending　strength,　absorption,　and　pore　structure　analysis　were　executed　on　polymer　latex　modified　cement　mortar.　The　test　results　in　lab　showed　that　with　the　additive　of　polymer　latex,　the　adhesive　bending　strength　between　mortar　and　old　concrete　was　enhanced,　the　water　absorption　coefficients　of　mortar　decreased,　and　pore　structure　of　mortar　was　improved.