As an important gasotransmitter, hydrogen sulfide having multiple biological roles cannot be easily probed in cells. In this study, a light controllable HS donor, Nap-Sul-ONB, derived from naphthalimide was developed. Under the irradiation of 365 nm light, a readily controlled stimulus, the donor could release COS to form HS and exhibit turn on fluorescence to indicate the release of payload and its cellular location. Besides, the ROS scavenging ability and cell protective effect of Nap-Sul-ONB against endogenous and exogenous ROS were studied. The results showed that upon 365 nm light irradiation, Nap-Sul-ONB could reduce the cellular ROS level and increase the survival rate of PMA-treated cells.