The invention discloses a combination air cooler, a circulating cooling water system based on the air cooler and a method. The combination air cooler comprises a case, a wet and cold portion, an air inlet, a spraying water tank, a technical medium outlet, a dry and cold portion, a hyperbolic air duct and a technological medium inlet, the wet and cold portion, the air inlet and the spraying water tank are sequentially arranged in the case from top to bottom, the technological medium outlet is positioned on one side of the case and led out from the wet and cold portion, the wet and cold portion sequentially consists of a spraying system and an evaporation cooling tube bundle from top to bottom, the evaporation cooling tube bundle consists of heat exchange tubes which are obliquely arranged, an included angle is formed between each heat exchange tube and the horizontal plane, the dry and cold portion is positioned above the wet and cold portion, the hyperbolic air duct is arranged above the dry and cold portion, and the technological medium inlet is positioned on one side of the case and led into the dry and cold portion. The circulating cooling water system based on the air cooler consists of a technological device cooler, a water pool, a circulating water pump and the combination air cooler which are sequentially connected along a circulating direction of sealed circulating technological media in the circulating cooling water system. The combination air cooler, the circulating cooling water system and the method have the advantages that electricity consumption and water consumption are saved during production, and an energy conservation effect is realized.