A micro high-performance liquid chromatographic method for the determination of prostaglandin E2 (PGE2) and the main prostaglandin E metabolite(PGEMT) in rat organs and human urine has been developed. Prednisolone was added to the sample as the internal standard. Extraction of PGs from biological samples was performed according to the following general procedure. The isolated PGs and the internal standard were subjected to reaction with dansyl hydrazine, separated by liquid chromatography on a μ Fine pack SIL C18 and determined fluorimetrically(Excitation wave length:365 nm, Fluorescence wave length: 505 nm). The mobile phase was methanol :acetonitrile : water : acetic acid(1 : 60 : 50 : 0.2). The flow rate was 8 μl/min. The standard deviation of the method was ±6.5 % for PGE2 and ±8.4 % for PGEMT. The detection and simultaneous quantitation of less than 10 ng of PGE2 and PGEMT is possible. Excretion values of adult men obtained by this method were PGE2, 5.1 - 15.2 ng/ml(n = 6, age 22-37); PGEMT, 2.7 - 44-2 ng/ml ; and with women, PGE2, 0.1 - 8.7 ng/ml(n=5, age 24-37); PGEMT 1.1 - 12.7 ng/ml. The proposed method is suitable for the pharmacological analysis of PGE2 and PGEMT in various rat tissues and human urine.