In this paper dielectric properties of La2-xBixMo2O9 (0 <= x <= 0.4) ionic conductors have been investigated. The frequency dependence of the dielectric permittivity and electric modulus data has been analyzed using Havriliak-Negami formalism. It has been observed that the shape parameters do not show any significant temperature dependence. The stretched exponent has been obtained from the fits of Kohlrausch-Williams-Watts function to the experimental data. The result indicates that the dielectric relaxation is highly non-exponential. Highly asymmetric decay function has been also obtained from the modulus data. (C) 2014 Elsevier Ltd. All rights reserved.