The present application relates to a secondary battery and an electrode member thereof. The electrode member includes an insulating substrate, a conducting layer and an active material layer. The conducting layer is provided on a surface of the insulating substrate, and the conducting layer includes a main portion and a protruding portion extending from the main portion, the main portion is coated with the active material layer, the protruding portion is not coated with the active material layer. The active material layer includes a first portion and a second portion, the first portion is positioned at an end of the active material layer away from the protruding portion, the second portion is positioned at a side of the first portion close to the protruding portion, and a thickness of the first portion is less than a thickness of the second portion.