Research on antimicrobial activity of essential oils from leaf of Syzygium tsoongii, Syzygium bullockii and Syzygium zeylanicum in Ha Tinh Province showed that essential oils from leaves of three species had antibacterial activity against three strains on the Gram (+): (Enterococus faecalis (ATCC 299212), Staphylococcus aureus (ATCC 25923), Bacillus cereus (ATCC 14579) and against Candida albicans (ATCC 10231). The essential oil from the leaves of Syzygium tsoongii and Syzygium zeylanicum had not antibacterial activity against Gram (-), while the essential oil from the leaves of Syzygium bullockii could be against 2 strains of Gram (-): Escherichia coli and Salmonella enterica strains.