The invention relates to a camshaft adjusting device (1) for an internal combustion engine and to a method for producing a camshaft adjusting device having a stator wheel (10) and a rotor wheel (11), wherein the rotor wheel (11) has a first body part (19) and a second body part (20), wherein a joining surface (19a) of the first body part (19) and a joining surface (20a) of the second body part (20) are joined to one another, and wherein depressions (21, 22) are formed in at least one of the joining surfaces (19a, 20a) in order to form the fluid ducts (17, 18) at least in sections. To provide a camshaft adjusting device (1) with an improved rotor wheel (11) which is formed from two body parts (19, 20) which can be joined to one another in an improved manner, it is provided according to the invention that at least one sealing means (25, 26) is provided in or on at least one joining surface (19a, 20a), which sealing means is designed such that the fluid ducts (17, 18) are sealed off and such that defined contact is realized between the joining surfaces (19a, 20a) which are placed on one another.