A　series　of　star-shaped　polycarboxylate　superplasticizers　(SPCEs)　possessing　different　arm　lengths　were　synthesized　by　changing　the　amount　of　chain　transfer　agent　in　the　polymerization　stage.　The　molecular　structure　information　was　determined　by　^Nuclear　Magnetic　Resonance　fHNMR)　and　gel　permeation　chromatography　(GPC).　The　effects　of　arm　length　on　the　adsorption　behavior　in　cement　pastes,　and　the　rheological　properties,　zeta　potential　and　hydration　heat　of　cement　pastes　were　also　evaluated.　SPCE　with　moderate　arm　length　exhibited　prominent　dispersing　capacity,　low　surface　tension,　strong　adsorption;　the　arm　length　was　directly　proportional　to　hydration　delay　and　reduction.　Furthermore,　the　moderate　arm　length　exactly　corresponded　to　strong　hydrophilicity,　suggesting　that　the　high-performance　superplasticizer　was　designed　towards　as　hydrophilic　as　possible.　The　aim　of　this　study　is　to　provide　a　theoretical　guidance　from　viewpoint　of　surface-interface　physicochemistry　in　designing　a　superplasticizer　with　great　potential　applications　in　concrete　engineering　requiring　good　workability　and　other　performances.　©　2018　American　Concrete　Institute.　All　rights　reserved.