Zn0.97Ce0.03S optical gas sensing material was successfully prepared by high temperature solid phase method. A gas sensor is composed of Zn0.97Ce0.03S gas sensitive film, simple gas chamber, micro optical fiber spectrometer and supporting software was built to detect H2S gas. The experimental results confirm that the H2S gas sensor has the characteristics of good stability and strong anti-interference ability. By using the Stern-Volmer equation of fluorescence quenching principle, it was found that the measured H2S gas concentration had a linear relationship with the fluorescence quenching signal of the sensitive element. The sensor has a fast response and can be used to detect with high sensitivity of the low concentration H2S gas.