Traditional composite infrared decoy, magnesium/teflon (Mg/PTFE), has been widely used in countering infrared guided weapons since its advent. However, with the development of infrared guidance technology, its drawbacks such as insufficient far-infrared radiation and high combustion temperature emerge, making it difficult to counter novel infrared guided weapons. To address this issue, a strategy of utilizing zirconium silicate (ZrSiO4) as an additive is proposed to improve the infrared radiation of infrared decoy. Therein, seven formulations with different ratios of ZrSiO4 are designed based on the basic formula of trilead tetraoxide/ magnesium/teflon (Pb3O4/Mg/PTFE) mixed powder. And the effect of ZrSiO4 serving as an additive on the performance of Pb3O4/Mg/PTFE infrared decoy is analyzed through experiments. First, initial experiments are conducted on the thermal decomposition characteristics of the basic formula (ZrSiO4 addition ratio is 0%) and its variant counterpart with 12% ZrSiO4. Subsequently, the combustion behaviors of the compacted formulation samples are examined using an infrared thermal imager operating within the 7.5–14 μm range, subsequently, the combution time, combution temperature, burning rate, radiation area, radiance, and radiation intensity of individual samples are computed. These results show that incorporation of ZrSiO4 reduces the intensity of the primary exothermic peak during the reactions with a mixed infrared decoy agent, yielding suboptimal thermal efficiencies. Furthermore, the combustion durations of the samples progressively increase with ZrSiO4 addition increasing, accompanied by consistent reductions in their combustion temperatures. Specifically, the sample reaction time peaks at 3.73 s at a ZrSiO4 addition ratio of 18%, while the combution temperature drops to a minimum value of 765.46 ℃. Moreover, the far-infrared radiance and radiation intensity demonstrate an initial-increase-then-decrease trend with ZrSiO4 addition increasing, thereby achieving the maximum values of 2461 W/(m2·sr) and 142 W/sr, respectively at a ZrSiO4 addition ratio of 6%. Furthermore, the far-infrared radiance and radiation intensity of the base formulation are enhanced when ZrSiO4 addition ratios are kept within 18% and 9% respectively. Based on the comprehensive analysis of the experimental data and considering the requirements for the infrared decoy in practical applications, a formulation with a ZrSiO4 addition ratio of 6% is adopted as an improved formulation for the Pb3O4/Mg/PTFE infrared decoy.