The invention discloses an air processor and floor cooling and heating combined system and a control method thereof, the air processor and floor cooling and heating combined system comprises an air processing subsystem and a floor cooling and heating subsystem, a heat pump host supplies water through an air processing water supply pipe, a surface air cooler in a variable air volume air processor, a flow regulating valve and an air processing water return pipe to form a water loop; in the variable air volume control processor, a fresh air valve, an air return valve, a frequency conversion fan, an air return temperature probe, an air outlet temperature probe, a humidification control valve, an electric heating device, the flow regulating valve and a coil pipe temperature probe are connected to a control panel. The control panel is provided with a variable air volume air processor control interface; the floor cooling and heating subsystem comprises a heat pump host, a water pump, a floor cooling and heating water supply pipe, a water dividing and collecting device, a floor coil pipe, a water return switch valve and a floor cooling and heating water return pipe which form a hydraulic loop, operation is simplified, system energy consumption is reduced, and the overall energy efficiency ratio is increased.