Objective:Volatile chemical components from butyl rubber closures were analyzed.Method:Using GC-MS and NIST chromatography library in the Xcalibur workstation to analyze the volatile substances from butyl rubber closures.Results:There were 21 substances volatiled from rubber closures measured in the experiment.And there was some difference between different rubber closures.Conclusion:The results of the experiment to analyze the volatile substances from rubber closures was a basis to study the compatibility between drugs and rubber closures.