Abstract: In order to learn and grasp the effect of refining process on the quality of Linseed oil,this research had taken GC- MS using headspace solid- phase microextraction and firstly compared the kinds of flavor substances and their relative contents before and after the refinement of flaxseed oil. The condition was that the adsorption temperature was 60 ℃,the sample size was 5 m L and the adsorption time was 30 min. The temperature program was set as follow: the initial temperature was 40 ℃,remaining unchanged for 2 min and rising to 160 ℃ at the rate of 4 ℃ / min and remaining unchanged for 1 min,then rose to 225 ℃ at the rate of 5 ℃ / min and remained unchanged for 5 min. The crude oil had 77 volatile constituents,including alcohols,phenols,acids,esters,carbonyls,heterocyclic compounds and alkanes with trace amounts of nitriles and amines,among which carbonyls and heterocyclic compounds were the main substances constituting crude oil's heavy roasted fragrant.However,product oil only had 18 volatile constituents,including carbonyls,alkanes,acids,a little amount of alcohols without heterocyclic compounds phenols and esters.So the flavor was more fragrant.