The work aims to determine the 4 kinds of benzophenones in paper packaging materials by GC-MS. The ultrasonic extraction method of benzophenone photoinitiators from paper packaging materials was optimized. The extract was then analyzed by GC-MS. Full scan and selected ion scan were used for the qualitative and quantitative analysis of each compound. The detection limits, quantification limits, linear ranges, relative standard deviations and recoveries of the established method were verified before the application in the real samples. The optimized ultrasonic extraction conditions were as follows:acetonitrile as extraction solvent, ultrasonic extraction twice and each extraction time of 20 min. The detection limits of 4 kinds of benzophenones were between 0.01-0.05 mg/L. The quantification limits were between 0.02-0.10 mg/L. Standard addition experiments showed that the relative standard deviations were between 2.0%-2.6% and recoveries between 98%-105%. The method, with low detection and quantification limits and relative standard deviations and high recoveries, is suitable for the analysis of 4 kinds of benzophenones in real paper packaging samples.