In this paper, the modelling and energy management strategy of high-temperature methanol reformed fuel cell hybrid power system are constructed. Firstly, using a combination of experimental data and one-dimensional mathematical modeling method for modular modeling of high temperature methanol reforming fuel cell model, including the combustion chamber model, reforming chamber model, cathode and anode pre-supply line model, cathode and anode model, as well as the electric stack model part. Secondly, the DCDC model, lithium battery model and electric motor model are established, and the hybrid powertrain is combined with the vehicle longitudinal dynamics model. The energy management strategy based on online efficiency point optimization is designed to reasonably allocate the power under variable operating conditions. The system decides the working mode of the system according to the demanded power of the bus, the value of the SOC of the power battery and the traveling speed of the bus. The simulation results of typical working conditions show that the driving speed of the bus can follow the specified target value curve well, and the fuel cell can work stably in the appropriate power range, with more than 60% of the high efficiency working points. Meanwhile, the value of power battery SOC is maintained within the specified range (30 similar to 45%), which avoids the fluctuation of the power system under variable operating conditions. Copyright (C) 2024 The Authors. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0/)