Polypyrrole films doped with BF4-,HSO4- and ClO4- were prepared by electrochemical method. Electrical conductivities of these samples and their temperature dependences were measured by four-probe method and VSC (voltage shorted compaction) method respectively. Experimental results indicate that the apparent temperature dependence of the conductivity as obtainted by the usual four-probe method, exhibits the character of typieal semiconductor, this feature is due to the contact resistance in the interblock or intergranular regions of the film. The measurement cannot reflect the true conductivity intrinsic to the doped polypyrrole film. However, the method devi-ced to short circuit the intergranular contact resistance does actually show the metallic temperature dependence of the conductivity of doped polypyrrole film, its conductivity increases with decreasing temperatures.When the polypyrrole film doped with BF4- was .partially reduced electrochemi-cally to a room temperature conductivity of 6-9 (Ω·cm)-1, the film exhibit a metal-semiconductor transition at 100 K as obtained by VSC measurement. IR-spectra indicates that the polypyrrole chain undergo certain structural changes during the electrochemical reduction process.