Shrinkage-reducing　polycarboxylate　superplasticizer　(SRPC)　is　a　new　type　of　concrete　admixture　with　both　shrinkage-reducing　and　water-reducing　effects.　Its　early　crack　resistance　to　concrete　will　affect　its　application　in　engineering.　In　this　paper,　the　effect　of　SRPC　on　the　early　crack　resistance　of　concrete　was　investigated　and　compared　with　polycarboxylate　superplasticizer　(PCE)　and　shrinkage　reducing　agent　of　low　molecular　weight　(SRA)　by　using　a　flat　crack　resistance　tester.　Moreover,　surface　tension　of　solution,　shrinkage　of　concrete,　pore　structure　of　cement　slurry,　and　cement　hydration　heat　were　analyzed　to　discuss　the　anti-cracking　mechanism　of　SRPC.　Experimental　results　show　that　SRPC　improved　the　early　crack　resistance　of　concrete.　When　0.　15%　(mass　fraction)　SRPC　and　1.　5%　(mass　fraction)　SRA　are　added　to　the　concrete,　although　the　former＇s　shrinkage　effect　is　not　as　good　as　SRA,　SRPC　still　show　better　early　crack　resistance.　Compared　with　PCE,　the　cracked　areas　of　SRPC　and　SRA　are　reduced　by　39.　33%　and　21.　34%,　respectively.　Mechanism　analysis　show　that　SRPC　reduce　the　shrinkage　of　concrete　by　reducing　the　surface　tension　of　the　pore　solution　and　changing　the　pore　structure,　which　is　similar　to　SRA.　Furthermore,　compared　with　SRA,　SRPC　also　delay　the　rate　of　cement　hydration,　reduce　the　heat　of　early　hydration,　inhibit　the　evaporation　of　water　inside　the　concrete,　thereby　improving　the　early　crack　resistance　of　concrete.　©　2021　Bulletin　of　the　Chinese　Ceramic　Society　Press.　All　rights　reserved.