Aluminum is characterised by its high calorific value, stable performance, and abundant reserves. It is a commonly used additive in solid propellants that are widely used in aerospace and underwater propulsion applications. As aluminum is a key component of these solid propellants, combustion temperature measurement of aluminum particles is crucial in investigating their combustion characteristics. This paper presents a method to determine the combustion temperature of aluminum particles in solid propellants. A combination of radiation imaging and Monte Carlo probability simulation is applied in the proposed method. Further, a numerical model is established to determine the surface temperature of aluminum particles. The method is validated through numerical simulation considering a target with a pre-set temperature distribution, as well as a practical implementation in solid-propellant combustion experiments. Results of the experimental analysis establish the reliability of the proposed method and also demonstrate the method's ease of operation, good practicability, and potential for future application.