Ethyl naphtho[2,1-b]furan-2-carboxylate (1) react with hydrazine hydrate gives naphtho[2,1-b]furan-2- carbohydrazide (2),Which on reaction with CS2/KOH gives 5-(naphtho[2,1-b] furan-2-yl)-1,3,4-oxadiazole-2(3H)- thione (3). The compound (3) on mannich reaction followed by reaction with phenyl hydrazine gives different 1- ((dialkyamino) methyl)-3-(naphtha [2,1-b]furan-2-yl)-4-(phenylamino)-1H-1,2,4-triazole-5(4H)-thione(4a-e). The structures of these compounds were established on basis of analytical and spectral data. The newly synthesized compounds were evaluated for their antibacterial and antifungal activities.