Flow distribution of kerosene in actively cooling panel is an important factor that constraints the cooling efficiency of the thermal protection system of scramjet. However, the flow mal-distribution is a common phenomenon in the realistic thermal protection system. In order to investigate this problem, a way to regulate the pressure drop via restriction orifice is proposed. The flow, heat transfer and thermal cracking process in cooling tube are calculated using a three-dimensional fluid-solid conjugated simulation method for supercritical cracked-kerosene. The results indicate that with an appropriate restriction orifice, the pressure drop under a lower heat flux can match with that under correspondingly higher heat flux in a same tube, which verifies the feasibility of pressure drop regulating using the restriction orifice. Therefore, this research could provides a design method of flow distribution in actively cooling panel of scramjet.