A series of novel thiazolidinones have been synthesized by reaction of various Schiff bases of coumarin with thiolactic acid. The reaction of 4-hydroxy coumarin with POCl3 yielded 4-chloro coumarin 2 and 4-chloro-3, 4', 3', 4"-tercoumarin 2a. Compound 2 was reacted with p-phenylene diamine to yield 4-[(4-aminophenyl)amino]-2H-chromen-2-one.Various Schiff bases of coumarin were synthesized by condensation of 4-[(4-aminophenyl)amino]-2H- chromen-2-one with different aldehydes. The structures of the newly synthesized compound were confirmed by IR, 1H NMR, 13C NMR and C, H, N analysis. The thiazolidinone derivatives were evaluated for their anti bacterial and antifungal activity by broth dilution method.