A valve timing adjusting apparatus for an engine comprises a housing unit and a vane rotor rotatably housed in the housing unit. The housing unit comprises a front plate, a shoe housing and a sprocket, wherein those elements are fixed to each other. A position determination pin is inserted through a through hole formed in the shoe housing and into a tapered hole formed in the sprocket, to position the shoe housing at a desired position with respect to the sprocket. Since a forward end of the position determination pin is brought into contact with an inner surface of the tapered hole, the positioning of the shoe housing with respect to the sprocket can be surely attained.