A pharmaceutical composition for treating osteoporosis which comprises as an active ingredient an effective amount of one or more compounds selected from the group comprising humulone, cohumulone, adhumulone, isohumulone, isocohumulone and isoadhumulone in combination with a pharmaceutically acceptable carrier or excipient. Humulone, cohumulone, adhumulone are the compounds belonging to α acids which are an ingredient extracted from hops, whilst isohumulone, isocohumulone and isoadhumulone are the compounds belonging to iso α acid derivatives which are isomers of α acids. The above described compounds have a bone resorption inhibiting activity and are useful for treating osteoporosis.