Viscosities of eight binary systems of n-butylamine, n-hexylamine, n-octylamine, n-decylamine, and n-dodecylamine with benzene and n-hexylamine, n-decylamine, and n-dodecylamine with cyclohexane have been measured at 303.15 K with an Ubbelohde suspended level viscometer. Based on Eyring's theory, values of excess Gibbs energy of activation ΔG*E of viscous flow have been calculated. Deviations of viscosities from linear dependence on the mole fraction and values of ΔG*E are attributed to H-bonding and to the size of alkylamine molecules. The free volume theory of Prigogine-Flory-Patterson in combination with the work of Bloomfield-Dewan has been used to estimate the excess viscosity Δ In η and the terms corresponding to enthalpy, entropy, and free volume contributions for 10 binary mixtures containing n-butyl, n-hexyl, n-octyl, n-decyl, and n-dodecylamine with benzene and cyclohexane.