An electrolytic copper foil capable of improving a capacity retention rate of a secondary battery, an electrode including the same, a secondary battery including the same, and a method of manufacturing the same. The electrolytic copper foil, which includes a first surface and a second surface opposite the first surface, includes a copper layer including a matte surface facing the first surface and a shiny surface facing the second surface, and a first protective layer on the matte surface of the copper layer, wherein the first surface has a peak density (PD) of 3 to 110, a texture coefficient [TC(220)] of a (220) plane of 1.32 or less, and a surface roughness (Rz) of 0.5 to 2.7 μm.