The method for separation and identification of three pairs of agarofuran epimers (alpha-and beta-dihydroagarofuran, alpha- and beta-baimuxinol, alpha- and beta-baimuxinol methyl ether) by HRGC and HRGC/MSD is described. The proportion of each pair of isomers was determined and the analytical procedure for isomers of sesquiterpenes was established. Thus, the correct synthetic route can be effectively guided and the study of agarofuran synthesis can be greatly accelerated. The method provides a reliable basis for identifying the products. MS data given in Table 2 may be useful for the identification of agarofuran derivatives.