A continuous variable valve duration apparatus may include a camshaft mounted to a cylinder head, a plurality of wheels mounted to the camshaft, of which a wheel key is formed respectively, and disposed on each cylinder, a plurality of cam portions of which a cam and a cam key are formed respectively, of which the camshaft is inserted thereto, of which relative phase angles with respect to the camshaft are variable, and disposed on the each cylinder, a plurality of inner brackets connected with the each wheel key and the each cam key, a plurality of slider housings of which the each inner bracket is rotatably inserted thereto, and disposed movable up and down direction of an engine, a guide shaft connecting the plurality of slider housings and a control portion moving a position of the guide shaft for changing rotation centers of the inner brackets.