This study was conducted to investigate the changes in fatty acid compositions of brain and liver of fertile chicken egg enriched with linoleic and linolenic acids. Sources of linoleic and linolenic acids were safflower(SO) and perilla oils(PO), respectively. Hens of each group were given diet with 1) safflower oil 8%, 2) safflower oil 6%+perilla oil 2%, 3) safflower oil 2%+perilla oil 6% or perilla oil 8%. After 14 days of feeding the diets, the layers were artificially inseminated to obtain fertile eggs. During the incubation, eggs were sampled on the 15th, 17th, 19th and 21st days for determination of fatty acid contents in brain and liver. Brain weights of chick embryos were not different among the dietary Treatments in all incubation days(p$gt;0.05) and its liver weight were similar except for the weight on the 17th incubation day(p$gt;0.05). The levels of linolenic and linoleic acid in liver tissues reflected the patterns of the acid composition in the egg yolk. Linolenic acid contents of SO8%, SO6%+PO2% SO2%+PO6% and PO8% was 174, 488, 1,275 and 1,893 ㎍/liver, respectively. Amount of eicosapentaenoic and docosahexaenoic acid were increased along with the amount of linolenic acid. In brain tissues, docosahexaenoic acid appeared to take the largest proportion of all the fatty acids for all dietary groups. The developing chick embryo had the ability to concentrate and maintain docosahexaenoic acid content in brain compered with a linolenic and eicosapentaenoic acid. Docosahexaenoic acid content of S08% group was lower, 918 ㎍/liver than those of other groups, 2,344∼2,624 ㎍/brain at 21st days(p$lt;0.05). The result indicated that the chick embryo had low ability to convert linolenic or linoleic acid to docosahexaenoic or arachidonic acid. Therefore it might absorb docosahexaenoic or arachidonic acid from egg yolk and concentrate these fatty acids in the tissues according to the specific property of each tissue.