A multi-temperature air conditioning system, comprising: an outdoor unit, in which a compressor, a first four-way valve, a second four-way valve and an outdoor heat exchanger connected through pipelines are arranged; at least one first indoor unit, in which a first indoor heat exchanger, a first throttling element and a first on-off valve are respectively arranged, wherein a first end of the first indoor heat exchanger is connected to the outdoor heat exchanger through the first throttling element and the first on-off valve, and a second end of the first indoor heat exchanger is connected to the compressor through the first four-way valve; and at least one second indoor unit, in which a second indoor heat exchanger, a second throttling element and a second on-off valve are respectively arranged, wherein a first end of the second indoor heat exchanger is connected to the outdoor heat exchanger through the second throttling element and the second on-off valve, and a second end of the second indoor heat exchanger is connected to the compressor through the second four-way valve; wherein the first four-way valve is respectively connected to an inlet of the compressor, the outdoor heat exchanger, the first indoor heat exchanger, and is capable of being connected to or disconnected from an outlet of the compressor; the second four-way valve is respectively connected to the inlet of the compressor, the outdoor heat exchanger, the second indoor heat exchanger, and is capable of being connected to or disconnected from the outlet of the compressor; and wherein the number of the first four-way valves corresponds to the number of the first indoor units, and the number of the second four-way valves corresponds to the number of the second indoor units; wherein a section flow path which could be connected or disconnected is further included, which connects the at least one first indoor unit to the at least one second indoor unit; and characterized in that the section flow path comprises: a first section on-off control valve located in the first indoor unit; and a second section on-off control valve located in the second indoor unit. an outdoor unit, in which a compressor, a first four-way valve, a second four-way valve and an outdoor heat exchanger connected through pipelines are arranged; at least one first indoor unit, in which a first indoor heat exchanger, a first throttling element and a first on-off valve are respectively arranged, wherein a first end of the first indoor heat exchanger is connected to the outdoor heat exchanger through the first throttling element and the first on-off valve, and a second end of the first indoor heat exchanger is connected to the compressor through the first four-way valve; and at least one second indoor unit, in which a second indoor heat exchanger, a second throttling element and a second on-off valve are respectively arranged, wherein a first end of the second indoor heat exchanger is connected to the outdoor heat exchanger through the second throttling element and the second on-off valve, and a second end of the second indoor heat exchanger is connected to the compressor through the second four-way valve; wherein the first four-way valve is respectively connected to an inlet of the compressor, the outdoor heat exchanger, the first indoor heat exchanger, and is capable of being connected to or disconnected from an outlet of the compressor; the second four-way valve is respectively connected to the inlet of the compressor, the outdoor heat exchanger, the second indoor heat exchanger, and is capable of being connected to or disconnected from the outlet of the compressor; and wherein the number of the first four-way valves corresponds to the number of the first indoor units, and the number of the second four-way valves corresponds to the number of the second indoor units; wherein a section flow path which could be connected or disconnected is further included, which connects the at least one first indoor unit to the at least one second indoor unit; and characterized in that the section flow path comprises: a first section on-off control valve located in the first indoor unit; and a second section on-off control valve located in the second indoor unit.