A metal porous body having a three-dimensional network structure, includes: a framework forming the three-dimensional network structure; and a coating layer having fine pores and coating the framework, the three-dimensional network structure including a rib and a node connecting a plurality of ribs, the framework including an alkali-resistant first metal, the fine pores having an average fine pore diameter of 10 nm or more and 1 μm or less, the coating layer including an alkali-resistant second metal and optionally including an alkali-soluble metal, the alkali-soluble metal being contained at a proportion of 0% by mass or more and 30% by mass or less with reference to a total mass of the framework and the coating layer.