Abstract: LPME-GC-MS was applied to the determination of 3 benzodiazepine drugs, i.e. eurodin, alprazolam and triazolam in blood with hollow fiber membranes. The optimized conditions found were as follows:① aperture of hollow fiber membrane of polyvinylidene fluoride was 0.1 μm; ② extraction solvent was xylene; ③ stirring rate of extraction was 500 r·min^-1; ④ extraction temperature was 30℃; ⑤ extraction time was 25 min; ⑥ pH of the sample solution was 9.0. The HP-5MS quartz capillary chromatographic column was used for GC separation and the selected ion monitoring mode was adopted in MS determination. Crossing internal standard method was used for quantitative. Linearity ranges of the 3 benzodiazepine drugs were all between 0.03 mg·L^-1 and 5.00 mg·L^-1 with detection limits (3S/N) in the range of 0.006-0.010 mg·L^-1. On the base of blank sample, test for recovery was made by standard addition method; values of recovery found were in the range of 95.0%-104%, with RSDs (n=6) in the range of 0.52%-6.3%.