Abstract: The present invention provides a thickening/foam-promoting agent having thickening/foam-promoting properties and a low odor, as well as a detergent composition containing the same therein. The thickening/foam-promoting agent is composed of the following component (A): (A) a compound represented by the following general formula (1): R1O—(PO)n/(EO)m—R2??(1) (wherein, R1 represents a linear alkyl or an alkenyl group having 8 to 10 carbon atoms, PO represents a propyleneoxy group, EO represents an ethyleneoxy group, an average added molar number n represents a number of 1.5 to 3.0, an average added molar number m represents a number of 0 to 1.0, and R2 represents a hydrogen atom or a methyl group), wherein, the content of an alcohol of the formula (1), wherein n=0, m=0 and R2 is a hydrogen atom, is not more than 3000 ppm, and the detergent composition contains the component (A) and a surfactant (B).