A detergent composition contains a polyglycerol monoalkyl ether, water, a fat or oil, and a polyol. The polyglycerol monoalkyl ether is present in the composition at a content of 1 to 50 percent by weight based on the total amount of the composition. The detergent composition is useable as a foamable cleansing agent kind to the skin, exhibits superior detergency for oily cosmetics, and is usable even under wet conditions.