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An efficient technique for the determination of multiclass pesticide residues (glyphosate, aminomethyl phosphonic acid (AMPA) and glufosinate) in four kinds of tea (green tea, black tea, Oolong tea and Puer tea) was developed based on ultra performance liquid chromatography. tandem mass spectrometry (UPLC-MS/MS). Samples were extracted with 0.05 mol/L NaOH solution, regulated pH value with HCl, followed by purification by Oasis HLB column, and then precolumn-derived with 9-fluorenylmethyl chloroformate (FMOC-CL) in borate buffer. All pesticide residues studied showed good linearity with correlation coefficient (R-2) greater than 0.99 in the concentration range of 5 - 1000 mu g/L. Limits of quantitation (LOQs) of three pesticide compounds ranged from 0.03 to 0.08 mg/kg (S/N = 10). Tea samples spiked with 0.1, 0.4 and 4 mg/kg showed the recovery ranging from 72.1% to 109.9%, and RSDs from 0.5% to 9.8% (n = 6). In addition, the validated method was applied to commercial samples, and all the detections were confirmed by acquiring transitions for each pesticide in samples.