The invention discloses an alternating current and direct current hybrid micro-grid system and a control strategy of the micro-grid system. The micro-grid system comprises multiple generation units, load, a distribution line for connecting the generation units and the loads, and a monitoring protection unit; each generation unit comprises a large power grid, grid-connected AC/DC (alternating current/direct current) of the large power grid, an energy storage system, a DC/DC (direct current/direct current) converter of the energy storage system, a wind power generation system, an AC/DC converter of the wind power generation system, a photovoltaic power generation system, a DC/DC converter of the photovoltaic power generation system, and a diesel generator; said load includes AC non-significant load, AC significant load, AC/DC load, DC significant load and DC non-significant load; the distribution line comprises a DC distribution line and an AC distribution line; the operating status of each energy conversion device can be monitored in real time by the monitoring protection unit, two operating ways such as grid connection and isolation of the system can be realized by different control strategies, the distributive generation unit and the energy storage unit realize coordination and cooperation by controlling energy storage DC/DC, photovoltaic DC/DC, and wind power AC/DC, so that the power supply reliability is improved and the significant load can continuously operate.