The invention relates to the technical field of air conditioning equipment, and in particular, discloses a double-temperature refrigerating and heating system, wherein a first cylinder, a first four-way valve, a first-grade throttle valve, an outdoor heat exchanger, a first-grade indoor heat exchanger, a gas-liquid separator, a second-grade throttle valve and a second-grade indoor heat exchanger of a compressor are connected through a pipeline to form a low-temperature evaporation loop; and a second cylinder, a second four-way valve, a first-grade throttle valve, an outdoor heat exchanger, a first-grade indoor heat exchanger and a gas-liquid separator of the compressor are connected through a pipeline to form a middle-temperature evaporation loop. The double-temperature refrigerating and heating system realizes switchover of refrigerating / heating modes through reversing of two four-way valves, realizes double-evaporation temperature refrigeration or double-condensation temperature heating, and effectively improves whole system energy efficiency; and obtained double-evaporation or double-condensation temperature can be widely applied to such places as freezing and refrigeration, air conditioner cold radiation and dehumidification, double-temperature heat source heat pump, air conditioner heat radiation and hot air or air conditioner heat radiation and living hot water.