A time-resolved fl uoroimmunoassay (TR-FIA) for determination of clenbuterol (CLB) in pig liver was developed. The limit of detection (LOD) was 0.02 ng g -1 and limit of quantifi cation (LOQ), 0.08 ng g -1 . Recoveries ranged from 89.3 to 117.9% for pig liver at spiked levels of 0.1-5 ng g -1 . The results obtained by the TR-FIA and enzyme-linked immunosorbent assay (ELISA) showed a good correlation. The established TR-FIA was applied for screening pig liver from the local market and confi rmed by gas chromatography-mass spectrometry (GC-MS). This proposed technique could be used for routine screening for drug residues.