The invention relates to an intelligent air purifying device with a sub 
machine considering indoor temperature, and belongs to the technical field of 
air purifiers. The intelligent air purifying device comprises an air inlet arranged outdoors, an air returning opening arranged indoors, an air purifying unit, indoor and outdoor detection sensors, a display controller and the indoor sub 
machine. The display controller judges the 
air pollution degree and the 
temperature difference according to an air 
pollutant concentration value and a temperature value which are sent back by the indoor and outdoor detection sensors, then the air return opening is opened or closed, and meanwhile an instruction is sent to enable the indoor sub 
machine to work. According to the intelligent air purifying device, the functions of a primary air 
system and an 
indoor air purifier are well combined, the 
indoor air is purified in a targeted mode through different control ways, and adjustment is carried out according to the indoor and 
outdoor temperature difference; meanwhile, the 
indoor air purifying sub machine is provided, the sub machine has various functions, and the intelligent air purifying devices realizes household life concepts of health, 
energy conservation, comfort, intelligence, convenience and the like.