By　using　the　simplex　centroid　design　method,　the　cementitious　system　of　cement-limestone　powder-slag　cement　pastes　was　designed,　and　then　effects　of　carboaluminate　on　the　anti-chloride　ion　penetration　performance,　Friedel＇s　salt　and　pore　structure　of　cement　pastes　were　also　investigated　through　X-ray　diffraction　analysis,　thermogravimetric　analysis　and　mercury　intrusion　porosimetry.　The　results　show　that,　the　chloride　migration　coefficient　of　cement　pastes　with　25%　and　50%　limestone　powder　increased　by　193.02%　and　534.50%,　respectively,　compared　with　that　of　cement　pastes　without　limestone　powder;　the　chloride　migration　coefficient　of　cement　pastes　with　25%　limestone　powder　and　25%　slag　decreased　by　85.98%,　compared　with　that　of　cement　pastes　with　50%　limestone　powder.　The　amount　of　carboaluminate　increased　with　the　increase　of　limestone　powder.　The　incorporation　of　slag　increased　the　content　of　carboaluminate.　The　diffraction　peaks　of　carboaluminate　were　not　found　after　RCM　test.　The　amount　of　Friedel＇s　salt　of　cement　pastes　with　0%,　25%　and　50%　limestone　powder　was　2.74%,　2.94%,　1.09%,　respectively.　Compared　with　cement　pastes　with　50%　limestone　powder,　the　amount　of　Friedel＇s　salt　of　cement　pastes　with　25%　limestone　powder　and　25%　slag　increased　by　363.30%.　The　more　limestone　powder　was　added,　the　larger　porosity　and　the　most　probable　pore　diameter　of　the　cement　pastes　were.　The　porosity　and　the　most　probable　pore　diameter　of　cement　pastes　with　25%　limestone　powder　and　25%　slag　decreased　by　31.23%　and　57.84%,　respectively,　compared　with　that　of　cement　pastes　with　50%　limestone　powder.　The　formation　of　Friedel＇s　salt　after　RCM　test　improved　the　pore　structure　of　cement　pastes.　©　2022,　Materials　Review　Magazine.　All　right　reserved.