The invention discloses a method for detecting 
fatty acid content in rice fat. The method comprises the following steps of: carrying out base-
catalysis methyl esterification and 
solid phase microextraction synchronously on a rice sample in a headspace 
bottle by means of a multifunctional sample 
injector, and then detecting and performing quantitative analysis on the 
fatty acid content in the rice fat after the rice sample enters a 
gas chromatography-tandem 
mass spectrum (GC-MS-MS). According to the invention, the on-line methyl esterification, the 
solid-phase microextraction and the 
gas chromatography-tandem 
mass spectrum technology are adopted, the five steps of methyl esterification, extraction, enrichment, sampling and detection are completed at the same time during one process, the operation is simple, and the consumed time is short; moreover, water acts as a base body during the methyl 
esterification reaction, so that the 
competitive adsorption of an extracting head to methyl 
alcohol and volatile substances is lowered, and the extraction and pre-enrichment of 
fatty acid methyl ester by the 
solid phase microextraction are improved effectively; and the minimum 
detection limit of fatty acid is 0.001-0.049 micro g / L, and is obviously lower than the minimum 
detection limit, 4.0mg / L, of an 
internal standard method which is used for performing 
quantitative determination on oil fatty acid.