Abstract: Objective To explore role of ROS in hypertrophic cardiomyocytes induced by the vasoconstrictors such as ET-1, Ang Ⅱ etc. Methods Neonatal cardiac myocytes were cultured and stimulated by ET-1 and Ang Ⅱ. Antioxidant N-acetylcysteine was used to block the intracellular synthesis of ROS . 2,7-dichlorofluorescin dictate was used to examine the intracellular ROS. We examined the expression of preproendothelin-1 gene by RT-PCR assay. Results We found that N-acetylcysteine pronouncedly block the synthesis of ROS and the expression of endothelin-1 gene. Compared with the control group, the fluorescence intensity of intercellular DCF-DA is increased in N-acetylcysteine and Ang Ⅱ group（+4.6%）, N-acetylcysteine and ET-1 group（+4.8%）, ET-1 alone（+108.8%） and Ang Ⅱ alone（+104.9%）. The expression of Prepro ET-1 increased by 3.8%, 2.9%, 52.4%, 51.1% correspondingly. Conclusion It indicates that ROS is pivotal in vasoconstrictor-induced cardiomyocyte hypertrophy, which was associated with increases in endothelin-1 gene expression in cardiomyocytes.