In order to study the effect of the ratio of oxidant to reducing agent on the performance of trilead tetraoxide/Mg/teflon mixed powder(Pb3O4/Mg/PTFE), keeping the formula of oxidant and changing the ratio of oxidant to reducing agent, 5 different formulations were designed. The uniformly mixed powder was compressed into a cylinder with a tablet press. The 7.5-14 ?滋m thermal imager was used to observe the combustion process of the tablet, and the burning time, mass burning rate, radiation area, radiation, and radiation intensity of each sample were obtained. The results show that with the increase of the proportion of reducing agent， the mass burning rate first increases and then decreases. When the ratio of oxidant to reducing agent is 1:1, the maximum mass burning rate is 5.03 g/s. The temperature of the flame increases with the proportion of reducing agent first and then decreases. When the ratio of oxidant to reducing agent is 1:2, the maximum temperature of the flame reaches a minimum of 754.29 ℃. With the increase of proportion of the reducing agent, the radiance grows first and then drops. When the ratio of oxidant and reducing agent is 1:1, the radiance reaches the maximum of 1 869.21 W·m-2·sr-1. The radiation intensity reaches the maximum of 97.61 W·sr-1. Visible in the 7.5-14 ?滋m band, when the ratio of oxidant and reducing agent is 1:1, the radiation characteristics of the sample is best.