Type conversion due to nitrogen ion irradiation in CdS thin films prepared by chemical bath deposition (CBD) is reported. The films were bombarded with various doses of nitrogen ions in the range 10(14)-10(17) ions/cm(2), at an energy of 130 keV. The electrical conductivity of the firms was found to increase with increase in nitrogen ion concentration. The temperature dependence of conductivity showed an activation energy of 0.06 eV, indicating shallow level formation due to implantation. Hot-probe measurements revealed p-type conductivity in implanted samples and n-type conductivity in unirradiated samples. X-ray diffraction results revealed CdS to be the predominant phase even after nitrogen ion irradiation.