The invention discloses a photovoltaic direct current micro-grid system, and relates to photovoltaic power generation. The system is provided with a high-voltage direct current micro-grid power supply system, a direct current application unit, a system monitoring and energy consumption measurement unit, a direct current generatrix and a DC/DC (direct current/direct current) rectification system, wherein the high-voltage direct current micro-grid power supply system comprises three direct current power supplies, i.e. a commercial power AC/DC (alternating current/direct current) direct current power supply, a photovoltaic power generation direct current power supply and a storage battery energy storage direct current power supply; the direct current application unit comprises a direct current data center unit, an electric vehicle charging station unit, a direct current air conditioning unit, a direct current illumination unit, a direct current home appliance unit and an expansion unit; the system monitoring and energy consumption measurement unit comprises an equipment monitoring unit and a workstation unit; according to the energy supply sequence of the direct current power supplies, power generated by the photovoltaic power generation direct current power supply is preferably used, the commercial power AC/DC direct current power supply is used for supplementing electric energy when the photovoltaic direct current power supply cannot supply sufficient power, and the storage battery energy storage direct current power supply is used for supplementing electric power when commercial power and photovoltaic energy sources are both insufficient. According to the system, the comprehensive photovoltaic utilization efficiency can be improved.