The carbon emission trading market does not cover small and micro entities, making the emission reduction contributions of microgrids difficult to quantify and trade. To address this issue, an optimal scheduling method of electric-hydrogen coupled microgrid with electric vehicles (EVs) under carbon inclusion mechanism is proposed. For emission reduction accounting, a multi-type carbon inclusion accounting method covering microgrid flexible emission reduction and hydrogen substitution emission reduction is established, with refined quantification based on time-varying carbon emission factors. For optimal scheduling, the flexibility of electric-hydrogen conversion equipment and EV charging/discharging is exploited, and an optimal scheduling model under synergistic dual incentives of carbon inclusion mechanism and demand response is constructed to minimize the comprehensive cost. Simulation results demonstrate that, through emission reduction trading and peak-shaving incentives, the dual incentive mechanism reduces the total carbon emissions by 6.59% and the comprehensive cost by 9.55%. Moreover, wind and solar curtailment is effectively reduced as the renewable energy penetration rate increases. The proposed method provides a feasible pathway for the low-carbon economic operation of user-side microgrids.