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This paper briefly introduced the harmfulness of polycyclic aromatic hydrocarbons (PAHs) and the source of PAHs in the pump rubber seals, and established a measuring method of 16 kinds of PAHs in pump rubber seals, by ultrasonic extraction coupled with GC-MS. The conditions for extraction were optimized, and the separation and determination conditions of 16 kinds of PAHs were defined. Through ultrasonic extraction, the selected ion monitor(SIM) was used to detect in pump rubber seals and quantitatively analyzed with the inner standard method. PAHs were spiked to evaluate the accuracy of this method. The average recovery varies from 80.9%～103.8% while the relative standard derivation of the precision experiment ranges from 4.80%～15.7%. This method is sensitive, accurate and suitable for the determination of PAHs in pump rubber seals.