PURPOSE: To provide the subject composition which has a cleaning effect comparable to those of a chlorogluorocarbon detergent and a chlorine compound detergent, scarcely has any adverse effect on resin and rubber and, in addition, has low toxicity so that it scarcely has any adverse effect on the environment.

CONSTITUTION: This detergent composition is composed mainly of an 8C or lower unsaturated hydrocarbon having a part of or all the hydrogen atoms substituted by fluoro and/or chloro groups and contains 2.5-25wt.% oxygen- containing solvent.