Abstract: GC-MS was applied to the determination of tetrabromobisphenol A in plastics. The sample was extracted with ethyl acetate for 20 min, and concentrated to dryness by N2-blowing. The residue was dissolved with 5.0 mL of methylbenzene, and derivatized with acetic anhydride. The derivatized products were separated on DB-5MS column and EI source was used in MS. Linear relationship between values of peak area and mass concentration of tetrabromobisphenol A was kept in the range of 0.1-100 mg·L-1. Tests for recovery were made by standard addition method with 2 samples of plastics (ABS and PS) as matrixes; values of recovery found were 97.0% for ABS and 94.2% for PS with RSD′s (n=5) less than 6.5%.