Abstract: As a self-excitation light sources, gaseous coating light sources is a kind of isotope illumination device which uses charged particles emitted by radioisotopes. For gaseous light sources, there is no need for maintenance and additional power, and it is not affected by temperature, humidity, altitude and technology, which makes it widely used in national economy. The coating process of gaseous light sources is one of the key techniques for the preparation of light sources. The single variable method by changing the ratio of compounds such as fluorescent powder, binder and curing agent were used to achieve a better formulation of water coating process, which was used in this coating process. The results showed that when the formulation ingredients contain PEO temporary binder was 7.0-7.5 mL, phosphor 13.16 g, deionized water 4.3 mL, additive 0.45 mL and curing agent （7.3-7.5）%, the coating effect was better.