Abstract: In a producing process of a sintered porous anode body of valve-metal for a solid-state electrolytic capacitor, molded pieces of the powder of valve-metal is sintered at a high temperature and at a lowered pressure in an atmosphere of an inert gas supplied at a fixed flow rate. Thanks to the usage of the inert gas, partial pressures of impurity elements can be suppressed and a gas emitted from the molded pieces in the sintering process can be washed out. Consequently, there is obtained a solid-state electrolytic capacitor in which the lead wire of the anode body is not easily bent down and which has a reduced leakage current and an increased withstand voltage.