Different types of linear bearings (guides) are widely used in practice in various equipment, as in many other areas of human activity. In particular, this applies to cylindrical guides (linear plain bearings) of reciprocating motion. However, despite their considerable distribution, in fact, there are no reasonable methods for calculating the wear and service life of not only metal but also metal-polymer linear bearings. According to the author's method, the influence of load, base diameter and radial clearance on the maximum initial pressures in this bearing was investigated within the plane contact problem of the theory of elasticity. Further, using the computational method according to the author's tribokinetic model of wear during sliding friction, the effect of the composite bushing wear on the change of the initial contact characteristics (contact pressures and contact angle) was evaluated. The forecast calculation of the service life of the bearing depending on the above factors is also carried out. Quantitative and qualitative regularities of dependence of contact pressures and a resource on the accepted factors are established.