It is well-known that the burning rate of the propellant for a solid rocket motor or a solid fuel ramjet increases as the cross-flow velocity increases. It has been shown, however, in many previous studies that the cross-flow temperature does not have a strong effect on the burning rate. In this study, the effect of the cross-flow temperature, on the burning rate was examined by using a double-base propellant and a small rocket motor. The augmentation of burning rate with cross-flow was found to have a weak dependence on the cross-flow temperature for temperatures above 1500 K. However, for cross-flow temperatures under 1500 K, the burning rate decreased significantly as the temperature decreased. Namely, a threshold temperature was found to exist in the effect of the cross-flow temperature. A simple model based on the energy and mass transfer between the cross-flow and the fizz zone was used to examine the effect of the cross-flow on the heat feedback from the gas phase. In this model, two parameters Φ c and Φ k were used. The parameter Φ c is related to the change of the fizz zone temperature due to turbulence in the fizz zone. The parameter Φ k is related to fizz zone physical properties such as thermal conductivity or flame geometry. The calculated results using these parameters had good agreement with the experimental data. The model showed that the parameter Φ c was important in determining the burning rate. Namely, the energy transfer between the cross-flow and the fizz zone due to turbulence increased the fizz zone temperature and the reaction rate in the fizz zone. As a result, the heat feedback from the gas phase increased and the burning rate also increased significantly.