In order to provide a novel detergent composition and an aerosol composition thereof that have a very low ability to attack rubbers and resins even while having cleaning and drying properties equivalent to those of conventional detergent compositions for brake cleaners, the compositions having such properties as: low danger of ignition and low risk of fire because the compositions are nonflammable; correspondence to a nonhazardous material under the Fire Service Act, obviating the need for a dangerous goods warehouse; no legal restriction on the storage quantity of detergent composition, which is to be used in large amounts; and also low toxicity and little environmental impact such as damage to the ozone layer, there are provided a detergent composition and an aerosol composition thereof that contain: (Z)-1-chloro-3,3,3-trifluoropropene, 1,1-dichloro-3,3,3-trifluoropropene, AMOLEA (registered trademark) AS-300, or another such HFO nonflammable fluorine solvent; and FluorinertTM FC-40, FluorinertTM FC-3283, or another such PFC nonflammable fluorine solvent.