The invention provides a heat exchange substrate assembly, a heat exchange module, a controller and an air conditioner. The heat exchange substrate assembly comprises a substrate body and a temperature sensing bulb, a cooling flow channel is constructed in the substrate body, the cooling flow channel is provided with an inlet pipeline, a flow adjusting device is arranged in the inlet pipeline, thetemperature sensing bulb is communicated with the flow adjusting device and is filled with a thermal medium, and the thermal medium can adjust the flow of the cooling medium flowing in the flow adjusting device along with the temperature change of a preset area detected by the temperature sensing bulb and/or the temperature change of the cooling medium in the inlet pipeline. According to the heatexchange substrate assembly, the heat exchange module, the controller, the air conditioner and the flow adjusting device, the flow of the cooling medium circulating in the flow adjusting device is adjusted in real time through the thermal medium, no external control component is needed, and the cooling load and the thermal load of the cooling fluid in the heat exchange substrate assembly are matched and balanced.