Abstract: The determinationmethod for rapeseed-oil from polished rice by GC was established. The rapeseed-oil in polished ricewas extracted by n-hexane. The oil was saponified and methylated and then was dissolved in isooctane.GC was finally used to determined. The method can determine rapeseed- oil illegally added in polished rice in the condition ofmethyl oleate, methyl linoleic acid, linolenic acid methyl ester and methyl mustard was respectively above 55.0, 45.0, 1.50 and 0.2 μg/mL. The results of reliability weremore than 95% and confidence factor was 2.