A novel class-specific molecularly imprinted polymer (MIP) beads for sulfonylurea herbicides was synthesized by precipitation polymerization using chlorsulfuron as the template molecule, 2-(diethylamino)ethyl methacrylate (DEAEMA) as the functional monomer, and trimethylolpropane trimethacrylate (TRIM) as the cross-linker. The mechanisms of recognition of MIP beads to the template molecule were evaluated by UV-spectrum and FTIR in the choosing and optimizing polymerization system experiment. The results showed that MIP beads contained the group which could interact with template molecule and its analogue by the hydrogen bonding specifically