The d. c. and a. c. (100 Hz-1 MHz) conductivities of HCl-doped polyaniline have been measured in the temperature range 77-300 K. At 77 K, the a. c. conductivity data, sigma(omega), can be described by the relation sigma(omega) = A omega(s), where the parameter slies close to unity and decreases with increase in the doping level. The ratio of measured a. c. to d. c. conductivity shows dispersion at 77 K, which decreases with increase in the doping level. This decrease is found to be sharp around pH similar to 3.0. In the temperature range 77-150 K, the observed d. c. conductivity data can be described by Mott＇s three dimensional variable range hopping (VRH) model. Scanning electron microscopy studies reveal a sharp change in structural morphology of HCl-doped polyaniline at a pH similar to 3.0. A strikingly remarkable structural morphology has been observed in the form of a channel at this pH value. This change is accompanied by a rapid increase in d. c. conductivity, dielectric constant, along with sharp changes in structural morphology, which indicates the existence of a doping-induced structural conductivity correlation in this system.