Dielectric relaxation measurements of Nylon-11 with substituted phenols p-Cresol, m-Cresol and o-Cresol mixture in different non-polar solvents CCl4, benzene and 1,4-dioxan for different concentrations over the frequency range of 10 MHz-20 GHz at 303 K have been carried out using Time Domain Reflectometry (TDR). Dielectric parameters such as static permittivity (ε0) and relaxation time (τ) were determined and discussed to yield information on the molecular structure and dynamics of the mixture. The dielectric constant and relaxation time were found to be high for Nylon-11 with p-Cresol in CCl4 compared to the other mixtures. © 2008 Elsevier B.V. All rights reserved.