Polymer is extensively applied in the cement system, while its interaction with cement clinker is still much elusive. The behavior of polymers, containing carboxyl, hydroxyl and ether groups respectively, at the tricalcium silicate (CS) interface is investigated utilizing molecular dynamics. The adsorption of electroneutral polymers by CS is promoted by H-bonds, rather than the Ca-O ionic bonding. Calcium dissociation from CS can be facilitated by polymer adsorption, while the dissociated calcium in the aqueous solution is barely adsorbed by the polymers. The results indicate the phenomenon that CS dissolution is restricted but the dissolved calcium from cement increases.