An ambient humidity control article for controlling ambient humidity within 55%-68%. The article includes a substrate having a predetermined water absorbability, and a humidity control layer coated on the substrate and made up of a humidity control composition. The amount of the composition coated on per cubic centimeter of the substrate is 0.54-0.74 grams. The composition includes water and at least one of citrate, lactate and formate. The citrate is at least one of sodium citrate, potassium citrate and calcium citrate. The lactate is at least one of sodium lactate and potassium lactate. The formate is at least one of sodium formate and potassium formate. The weight percentage of each of the citrate, lactate and formate in the composition is 33.3%-84.2%. The water absorption amount of the substrate is not less than 0.5 grams per cubic centimeter.