A model consisting of two parallel pipes with common inlet and outlet manifolds was established and used to run simulation and experimental study on the flow rate distribution of cracked hydrocarbon fuel in parallel pipes under supercritical pressure. Both simulation and experimental results indicated that mass flow rate and fuel temperature distribution of cracked hydrocarbon fuel in parallel pipes was closely related to the difference in fuel density in pipes. Two deviation amplification mechanisms were found. In addition, the mode of mal-distribution varies with thermal deviation and the distribution was effectively improved by the increase of pressure. And the total mass flow rate could hardly have any effects on the flow rate distribution. All these results could be used to help the full utilization of fuel heat sink and avoid over-temperature. (C) 2015 Elsevier Ltd. All rights reserved.