The cationic polymerization of cardanol using borontrifluoridediethyletherate as initiator has been investigated by gel permeation chromatographic techniques. The molecular weight and molecular weight distribution of the polymer at different temperatures and various initiator concentrations were studied, and the polymerization conditions have been optimized as 140°C with an initiator concentration of 1%. The reaction was found to follow first-order kinetics with respect to the monomer. The activation energy and rate constants for the system have also been evaluated. The polymer has been characterized by IR, 1H and 13C-NMR spectra.