To encourage electric buses to participate more effectively in vehicle-to-grid interactions, a multi-timescale optimal scheduling strategy for electric buses considering auxiliary service incentive mechanism is proposed. First, taking the distribution network as the research background, and based on the forecast data of workday and weekend base loads as well as wind and solar power generation, a day-ahead coordinated scheduling plan for wind and solar power generation and electric buses is formulated, with the objectives of maximizing the net revenue of wind and solar generation and minimizing the dispatch cost of electric buses. Second, based on the day-ahead coordinated scheduling plan, the forecast data are corrected through intra-day rolling updates. An intra-day scheduling strategy for electric buses is developed with the goals of maximizing new energy consumption and minimizing the standard deviation of the net load in the distribution network. Finally, the auxiliary service incentive mechanism for electric buses is introduced into the multi-timescale optimal scheduling strategy, while the superiority of the proposed strategy is verified through case analyses.