To investigate fatty acid constituents and relative compositions in the fluid of the follicles, oviducts, uterine body and uterine body in Korean native cow, the fluids of the reproductive tract were analyzed using gas chromatography. The samples were taken from various reproductive tract of 23 Korean native cows. q. Caprylic acid (C8:0), myristic acid(C14:0), palmitic acid(C16:0), palmitoleic acid(C16:1), stearic acid(C18:0), oleic acid(C18:1), linoleic acid(C18:2), arachidonic acid(C20:4) were found in the reproductive tracts of the cows, which made 8 kinds of fatty acid in total. 2. Palmitic acid, oleic acid, stearic acid were predominant with 35.67%, 24.98% and 17.52%, respectively. while low levels of fatty acids(<5%) were myristic acid, palmitoleic acid and caprylic acid with 1.75%, 1.28% and 2.69%, respectively. 3. Two kinds of polyunsaturated fatty acids, linoleic acid arachidonic acid were found in the reproductive tracts of cows. 4. Palmitic acid among saturated fatty acids and oleic acid among unsaturated fatty acids were the highest level in all of the reproductive tracts. 5. The Highest level of arachidonic acid was found in the uterine horn. 6. The sum of the palmitic acid and oleic acid were 61.72%, 63.72%, 57.66% and 57.65% for the fluid of follicle, oviduct, uterine horn and uterine body of the cows, respectively. 7. The relative compositions of palmitic acid, palmitoleic acid and caprylic acid were higher during the luteal phase than during the follicular phase. 8. The relative compositions of arachidonic acid was higher during the follicular phase in the fluid of uterine horn and uterine body of the cows. 9. The long chain fatty acid, the palmitic acid, stearic acid, oleic acid and linoleic acidshowed higher relative compositions during the follicular phase(86.49%∼95.51%) than during the luteal phase(85.64%∼88.93%).