To obtain a detergent which is intentionally allowed to absorb water in the atmosphere by utilizing the absorption characteristics of calcium chloride.

This detergent comprises calcium chloride and one kind selected from the group consisting of (1) a surface active agent, (2) an organic neutral agent, (3) an inorganic neutral agent, (4) an organic acidic agent, and (5) an inorganic acidic agent or a combination of a plurality of them. The agents (2) to (5) include, e.g. sulfamic acid and sodium sulfate. As the compounding ratio of components (1) to (5), each of components (1) to (5) is 0.1-20 pts.wt. based on 100 pts.wt. calcium chloride.