The friction and wear of various materials and audio heads sliding against magnetic tapes were studied. Magnetic materials such as Permalloy, Sendust and hot-pressed ferrite (HPF) and some other non-magnetic materials were used as material specimens. Three types of audio heads for cassette tape recorders were used as the head specimens. Their magnetic cores were made from ordinary Permalloy, hard Permalloy and HPF. An experiment using a conical diamond slider was carried out to study the wear resistance of various materials. The specific wear rates of the various material specimens and components of the heads such as the core, shield plate and epoxy resin were measured using the Knoop indentation technique. Wear did not occur uniformly over the surfaces of the Permalloy heads. This irregular wear was examined in detail and its origin is discussed. The specific wear rates of Permalloy and HPF are of the order of 10 −5 mm 3 N −1 m −1 and 10 −6 mm 3 N −1 m −1 respectively and that of epoxy resin is of the order of 10 −4 – 10 −5 mm 3 N −1 m −1. The coefficient of friction of an HPF head is about 0.3, while that of both types of Permalloy head is about 0.7. It is concluded that the mechanism of wear by magnetic tape is not entirely due to the abrasive action of the magnetic powder in the tape but is also partially adhesive in nature.