The analysis of several pyrethroid insecticides in the Chinese herbal medicine (CHM) Tian Hua Fen (Radix trichos Anthis) by multiresidue (ML) gas chromatography (GC) method is described. Insecticides were extracted from Tian Hua Fen (5g) by petroleum ether and cleaned up by natural aluminum oxide; purified extracts were analyzed by GC using electron capture detection (ECD). The extraction method has shown good recovery on various spike standard levels (1, 0.1 and 0.01 mg kg^-1). Pyrethroid insecticides are quantified using backed column gas chromatography. Good linearity ranges (r>0.99) were observed for all compounds. The average recoveries (over 82%), standard deviation, coefficient of variation (<16) and variances of recoveries were calculated for each analyte for each fortification level independently. Individual detection limits were in the range 0.0007–0.0028 mg kg^-1. Limits of quantification varied from 0.0022 to 0.0092 mg kg^-1. Method performance was characterized and validated according to (ISO 17025 and/or GLP). Selectivity, accuracy, precision, repeatability, reproducibility, limit of detection and limit of quantification were within acceptable ranges.