Kinetics of mixed-gas adsorption by using the Statistical Rate Theory is studied. Applying the adsorption lattice model two cases are investigated: when adsorption occurs like on the homogeneous surface and when energetic heterogeneity of adsorption system can be described by the rectangular adsorption energy distribution function. The model of calculations offers possibility of theoretical prediction of the rate of adsorption/desorption of mixture components by using the single-gas equilibrium and kinetic data. Possible changes of adsorbate concentration near the adsorbing surface are also taken into account. The obtained theoretical expressions were verified using real adsorption systems. (C) 2008 Elsevier B. V. All rights reserved.