A positive electrode for a secondary battery includes a positive electrode current collector, and a positive electrode mixture layer containing a positive electrode active material and provided on a surface of the positive electrode current collector, wherein the positive electrode active material contains a lithium-containing composite oxide which has a layered structure, and in the lithium-containing composite oxide, nickel occupies 80 atom % or more of a metal other than lithium, and the positive electrode mixture layer has a carbon fiber having an outermost diameter of 5 nm or less, and the carbon fiber is contained by 0.1 parts by mass or less relative to 100 parts by mass of the positive electrode active material.