A new pyrazole derivative 1-phenyl-3-methylthio-4-cyano-5-acrylicacidcarbamoyl-pyrazole (PMTCAACP) was synthesized and chosen as a complexing monomer for the preparation of surface-grafted ion-imprinted polymers for selective solid-phase extraction of thorium(IV). The silica gel, modified with maleic anhydride, was prepared as a carrier material. In the ion-imprinting process, Th(IV) was complexed with PMTCAACP, and then imprinted in the polymers grafted to the surface of modified silica gel. Subsequently, the template Th(IV) ions were removed with 6 mol/L HCl solution. The obtained ion-imprin...