The invention discloses a heat metering device for cold water and hot water, which realizes that bidirectional flow for water inflow and backwater is detected, a temperature signal and a flow signal are wirelessly transmitted without external connection leads, and operations of wireless charging and wireless meter reading can be carried out. The wireless heat meter is suitable for cold water and hot water. The heat metering device is provided with a reflection ultrasonic flow meter, a temperature sensor, a Zigbee controller and an LCD liquid crystal display device. The reflection ultrasonic flow meter is connected in series in a water inlet (or backwater) pipeline; the temperature sensor is arranged inside the flow meter; the Zigbee controller is arranged on the upper part of the flow meter; and the LCD liquid crystal display device is arranged on the top of the flow meter. Hardware, circuits and software of two devices which are matched to use are all same, the software firstly automatically sets a device connected with a high-temperature pipe to be a master node mode, and sets a device connected with a low-temperature pipe to be an auxiliary node mode when the two devices are used, the two modes can be regularly switched, the faults are automatically switched and a double-controller is simultaneously operated in parallel. The heat metering device for cold water and hot water is suitable for severe environment, such as strong electromagnetic interference, high voltage, high temperature, high humidity and the like, and is widely applied to a cold water/hot water concentrated air-conditioner heating system, thereby realizing separate metering for one meter each household.