Hydrogen sulfide is a vital signaling molecule which holds a pivotal position in numerous biological functions. In this research, two novel "OFF-ON" fluorescence probes named YNO and TNO were designed based on the nitroso recognition group to detect H 2 S. Both YNO and TNO performed outstanding response rate and linear relationship between the fluorescence intensity and the concentration of H 2 S. YNO possessed larger Stokes shift and longer emission wavelength. TNO had lower limit of detection. In addition, YNO was successful applied to sense endogenous and exogenous H 2 S and target endoplasmic reticulum (ER) in Hela cells.