Home security device and control method thereof, home security system and air conditioner

The invention discloses a home security device and a control method thereof, a home security system and an air conditioner. The home security device comprises a thermal radiation unit, a first processor and an alarm unit. The method comprises the steps that the thermal radiation unit acquires thermal radiation quantity information of a regional space in which the home security device is arranged; the first processor analyzes the thermal radiation quantity information of the regional space and determines whether the regional space is in the abnormal state; and the alarm device emits an alarm signal when the first processor determines that the regional space is in the abnormal state. The problems in the prior art that intelligent monitoring devices judge the home security only by monitoring frame fluctuations and the accuracy is poor can be solved and the accuracy of home alarm can be enhanced.