The electroreduction of CO2 suffers from competing HER effect, low product selectivity and low stability towards broader potential range thus the design and synthesis of novel electrocatalysts is a pursuit for scientists to further realize the high electroreduction efficiency and selectivity for years. Herein we report a work on the electrocatalytic reduction of CO2 into formate using scarce single Mo atom loaded ultrathin N doped graphene. When using 4 mol% ionic liquids (ILs) as the electrolytes the electrocatalyst was very efficient and realized impressed promotion than conventional N doped graphene. The faraday efficiency of electrocatalytic CO2 into formate on Mo@NG got enhanced over 100% than N doped graphene and reached formate yield of 747 mmol/(gcatal·h). Our results might inspire the fabrication and construct of low-cost, high-efficiency electrocatalysts for CO2 reduction fuel production in the future.