A metal capacitor in which an electric conductivity is significantly improved by applying a metal material for an electrolyte and a manufacturing method thereof is provided. The capacitor includes: a terminal increase-type metal member comprising a groove forming portion; a metal oxide layer being formed on the terminal increase-type metal member; an insulating layer being formed on the terminal increase-type metal member; a plurality of main electrode layers being formed in a groove forming portion; a plurality of conductive connecting layers being formed on the plurality of main electrode layers and the insulating layer; a first lead terminal being selectively connected to the first and the second electrode withdrawing portions of the terminal increase-type metal member; a second lead terminal being connected to the main electrode layer of the terminal increase-type metal member; and a sealing member sealing the terminal increase-type metal member connected to the first and the second lead terminals to externally expose the first and the second lead terminals.