For a search of biologically active compounds, extracts of various marine animals have been tested for their anti-allergy activity. Water extracts of Ligia exotica and sea pen (dried soaking in $H_2O$) showed strong histamine release inhibitory effects (L. exotica:75.6\%, sea pen: 78.5\%). The Ligia exotica collected in Pusan and sea pen (Pennatura Sp.) collected from thailand were homogenized with water and centrifuged. The L. exotica and sea pen extracts were chromatographed on gel column(Bio-Gel P-2 and Sephadex G10) and low pressure LC. the active fractions collected were subjected to recyclic preparative HPLC(GS 320 and ODS column). Many amino acids (Gly, Bet, Phe and Tyr), nucleosids (Uridine, Thymidine, Inosone, 2``-deoxyinosine, Guanosine, 2``-deoxyguanosine, 2``-Deoxyuridine) and bases (Uracil and Hypoxanthine) were isolated and elucidated by spectral data of $^1$Hnmr, $^{13}$C nmr, UV and MS. Especially, Trp-1 which has structural similarity with tryptophan, showed very strong histamine release inhibitory effect of 94\%. Other constituents which have interesting biological activity and structural features are being under investigation.