Abstract: Since the temperature field conditions of the existing intake heating test device cannot meet the index requirements of a certain engine, the structural design, test scheme, temperature field evaluation method, and steady-state and transition state test scheme of the new intake heating device are carried out to ensure that the engine inlet temperature field meets the requirements. This paper makes a numerical simulation analysis of the temperature field uniformity using four engine inlet conditions and using the circumferential non-uniformity method. The simulation results show that the circumferential non-uniformity of the temperature field ≤ 1%. At the same time, the combined tests of a turbofan engine and the intake heating device under multiple operating conditions were carried out. The steady-state tests show that the circumferential non-uniformity of the temperature field at the highest engine speed was 0.4395%, and the temperature field distribution was consistent with the simulation results. The results of the transition state test show that the inlet temperature field unevenness is related to the engine inlet temperature change rate, and the inlet temperature regulation method is the key to meet the requirements of temperature field circumferential unevenness under different engine working conditions. The results of simulation analysis and joint test show that the newly designed inlet heating device can meet the requirements of circumferential unevenness of the inlet temperature field in the multi-condition engine test.