Flexible Electrode, Secondary Battery Including the Same, and Flexible Secondary Battery

A flexible electrode includes: a current collector; an electrode layer positioned at a top of the current collector; a first support layer positioned at a top of the electrode layer; and a second support layer positioned at a bottom of the current collector, wherein each of the first support layer and the second support layer is a conductive coating layer-containing porous polymer substrate including a porous polymer substrate, and a conductive coating layer positioned on a surface of the porous polymer substrate and including a conductive material and a dispersing agent, and the porous polymer substrate is a non-woven web provided with a plurality of polymer fibers and a pore structure interconnected by the plurality of polymer fibers.