The synthesis and antimicrobial activity of 7 new 6-hydroxy-2,5,7,8-tetramethyl-N'-(2-oxoindolin-3-ylidene) chroman-2-carbohydrazide derivatives (4-10) were reported against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumonia, Salmonella Typhi, Vibrio cholera, Candida albicans and Aspergillus niger. Some of the tested compounds were showing activity against several of the microorganisms. In particular, compounds 6 and 7 were found to be of potent activity against bacterial strain, Escherichia coli (15 mm) and compound 4 and 5 against fungal strain, Candida albicans (16 mm) at a concentration of 100 μg/ml. The highest MIC of 12.5 μg/ml was shown by compound 7 against E. coli