Polyaniline perchlorate (PAP) was synthesized by the chemical oxidation of aniline using ferric perchlorate as a strong oxidant. The electrical conductivity of PAP was measured at temperatures from - 170 to 25$^{circ}C$. It is suggested from the conductivity measurements that the conduction mechanism for PAP is a polaron hopping conduction. From the dependence of resistivity on the reciprocal temperature, the activation energy was computed to be 0.072 eV. From the comparison of the ESR parameterks and conductivity at 25$^{circ}C$ for the polyaniline-based conducting polymers, the conductivities of PAP, PATFB and PATS increase with increasing ${Delta}H_{pp}$, decreasing A/B ratio and decreasing g-value, respectively. It is shown by TGA results for PAP, PATFB and PATS that the maximum weight loss rates (Pr) are 0.185 (at 269$^{circ}C$ ), 0.366 (at 324$^{circ}C$) and 0.23 mg/min (at 338$^{circ}C$), respectively.