A polycrystalline silicon rod manufacturing method wherein silicon cores are arranged in a reactor vessel, a source gas containing silane compounds is supplied into the reactor vessel, and polycrystalline silicon is deposited on the silicon cores electrically heated using a CVD method, the method comprising a high-frequency current applying process for heating the polycrystalline silicon rods by applying through the polycrystalline silicon rods current having a frequency of not less than 2 kHz and less than 200 kHz from a variable-frequency, high-frequency power source (15L, 15H, 15C), wherein the high-frequency current applying process comprises supplying a high-frequency current to polycrystalline silicon rods whose diameter reaches a predetermined value D 0 of 160 mm or more due to the deposition on series-connected polycrystalline silicon, and in the high-frequency current supplying process, the frequency of the high-frequency current is selected corresponding to variation in surface temperature of the polycrystalline silicon rods to the extent that a skin depth at which the high-frequency current flows through the polycrystalline silicon rods is in the range of not less than 13.8 mm and not more than 80.0 mm, wherein a gas containing trichlorosilane is selected as the source gas, and a surface temperature of the polycrystalline silicon rods is controlled in a range of not less than 900°C and not more than 1250°C to deposit polycrystalline silicon, the selection of frequency of the high-frequency current is provided among at least two frequencies, and the high-frequency current supplying process comprises maintaining the surface temperature of the polycrystalline silicon rods wherein when there is a sign that the surface temperature of the polycrystalline silicon rods lowers under the condition that the current is supplied at a constant amount of energization, and characterized by: i) the frequency of the high-frequency current is switched to the side of the low-frequency and the amount of energization is also increased; or ii) the frequency of the high-frequency current is switched to the side of the high-frequency while maintaining the amount of energization. the method comprising a high-frequency current applying process for heating the polycrystalline silicon rods by applying through the polycrystalline silicon rods current having a frequency of not less than 2 kHz and less than 200 kHz from a variable-frequency, high-frequency power source (15L, 15H, 15C), wherein the high-frequency current applying process comprises supplying a high-frequency current to polycrystalline silicon rods whose diameter reaches a predetermined value D 0 of 160 mm or more due to the deposition on series-connected polycrystalline silicon, and in the high-frequency current supplying process, the frequency of the high-frequency current is selected corresponding to variation in surface temperature of the polycrystalline silicon rods to the extent that a skin depth at which the high-frequency current flows through the polycrystalline silicon rods is in the range of not less than 13.8 mm and not more than 80.0 mm, wherein a gas containing trichlorosilane is selected as the source gas, and a surface temperature of the polycrystalline silicon rods is controlled in a range of not less than 900°C and not more than 1250°C to deposit polycrystalline silicon, the selection of frequency of the high-frequency current is provided among at least two frequencies, and the high-frequency current supplying process comprises maintaining the surface temperature of the polycrystalline silicon rods wherein when there is a sign that the surface temperature of the polycrystalline silicon rods lowers under the condition that the current is supplied at a constant amount of energization, and characterized by: i) the frequency of the high-frequency current is switched to the side of the low-frequency and the amount of energization is also increased; or ii) the frequency of the high-frequency current is switched to the side of the high-frequency while maintaining the amount of energization. i) the frequency of the high-frequency current is switched to the side of the low-frequency and the amount of energization is also increased; or ii) the frequency of the high-frequency current is switched to the side of the high-frequency while maintaining the amount of energization.