Abstract: In order to study the migration of photoinitiators (PIs) in the indirect packaging materials, a GC-MS/MS method was developed to determine the specified migration of 18 PIs, modified polyphenylene oxide (MPPO) was used as a simulator. PIs adsorbed by MPPO was extracted with acetonitrile, the extract then was solvent-displaced by n-hexane-ethyl acetate (v/v 3 : 7), filtered with organic filter membrane, separated on DB-5MS capillary column, analyzed by MS/MS and quantified by inner standard. The results showed that: 1) All of the 18 PIs were well separated in 26 min and had good linear relationship (R²> 0.997) within 0.01-5.00 mg/L. The recoveries of 18 PIs ranged from 86.4% to 123.8% with relative standard deviation less than 8.8% and the limits of detection (LODs) from 0.001 to 0.021 mg/kg. 2) Within the migration range of 0.02-30.00 μg/g, the relative standard deviation of repeatability and reproducibility ranged between 6.3%-21.4% and 13.5%-22.3%, respectively. 3) The migration rates of PIs in real samples significantly negatively correlated to their molecular weights and boiling points. 4) Vacuum aluminized inner liner could effectively barrier PIs migration.