Leathereating beetles, i.e., Anthrenus shaeff and Attagenus latr., are harmful pests causing damage to museum exhibits and materials containing keratin. The investigation, using an olfactometer, showed that the beetle's response to smells of various substances depends both on the species of the beetle and on their physiological condition. Moth-repellents do not repel leather beetles. To protect museum exhibits, combinations of repellents are to be used based upon tests with species of insects causing problems. Use of the olfactometer is explained.