In order to realize the efficient utilization of energy, as well as reduce carbon emissions and source load uncertainty, this paper proposes a multi?time?scale low?carbon collaborative optimal scheduling strategy for integrated energy systems considering hydrogen energy coupling and stepped carbon trading mechanism. Firstly, in order to effectively reduce the carbon emission level of the system, a ladder carbon trading mechanism is introduced, and a low?carbon economic scheduling model is established. Secondly, to give full play to the efficient and clean characteristics of hydrogen energy, a hydrogen energy coupling equipment model based on electrolytic cell, hydrogen fuel cell and methane reactor is established, and a multi?source energy storage model of electricity, heat and hydrogen is developed. Finally, with a purpose to reduce the impact of source and load prediction errors on the optimal scheduling of the system, and taking into account the response differences of electricity, heat, gas under different time scales, the scheduling models for day?ahead and intra?day multi time scale are constructed, respectively. The example analysis shows that the introduction of hydrogen energy coupling system and stepped carbon trading mechanism can not only improve the operation economy, but also reduce the carbon emissions, and the proposed multi time scale scheduling strategy can effectively suppress the power fluctuation, and reduce the uncertainty of the system source load.Key words: hydrogen energy coupling; multi time scale; carbon trading mechanism; collaborative optimization; multi?source energy storage