The invention discloses an air conditioner system based on solar energy and underground cold water. The air conditioner system based on solar energy and underground cold water comprises an underground cold water circulating system, a solar water heater circulating system and an indoor heat exchange system. According to the underground cold water circulating system, low-temperature underground water is pumped to a heat preservation water tank through a make-up pump, stored and then pumped to a top plate heat exchange device of the indoor heat exchange system through a circulating water pump to exchange heat so as to reduce the indoor temperature; and according to the solar water heater circulating system, the water temperature is increased through solar energy, the water is conveyed into a heat storage water tank and stored, then the water is conveyed into a heat exchange device through a circulating water pump, the hot water obtained through heat exchange is supplied to a floor radiation heat exchange device to increase the indoor temperature, and meanwhile the hot water in the heat storage water tank can also be used as domestic hot water. According to a solar fresh air cooling and dehumidifying system, a solar cell panel generates and supplies electricity to a semiconductor refrigerating chip set for providing electricity for cooling a water source, the indoor temperature is lowered through the cooled low-temperature water by means of a fresh air ventilator, and the humidity is adjusted. The air conditioner system is simple in structure, renewable energy sources are reasonably used, the water resources are recycled, and the cost is saved.