A sensitive molecularly imprinted electrochemical sensor was fabricated for selective detection of caffeine by electroploymerization of o-phenylenediamine on glassy carbon electrode（GCE） modified with multi-walled carbon nanotubes（MWNTs）.The template can be quickly removed in 0.1 mol?L-1 HCl.The molecularly imprinted sensor was characterized by cyclic voltammetry and linear sweep voltammetry.The molecular imprinted polymer based sensor displayed an excellent recognition capacity toward caffeine.The linear sweep voltammetry peak current was linear in the analyte concentration range of 2.0×10-7-2.0×10-5 mol?L-1,with a detection limit of 4.0×10-8 mol?L-1.The sensor was applied in the determination of caffeine in Tieguanyin teas,with recoveries of 94%-106%．