A valve timing control device, comprising: a drive side rotating member that is adapted to rotate in synchronization with an engine crankshaft; a driven side rotating member, disposed so as to be rotatable relative to the drive side rotating member on the same axis as the drive side rotating member, that is adapted to rotate together with a camshaft that is adapted to open and close at least one of an inlet valve and exhaust valve of the engine; and a locking mechanism that is adapted to lock the relative rotation phase of the drive side rotating member and driven side rotating member at a lock phase, wherein the locking mechanism includes a regulating body (61a, 61b) and n (n is a positive integer) stepped portions (62a to 62d) with which the regulating body (61a, 61b) is adapted to engage, allowing a relative rotation bringing the relative rotation phase nearer to the lock phase and regulating a relative rotation whereby the relative rotation phase is distanced from the lock phase, and the relative rotation phase is regulated in steps from a most retarded phase or most advanced phase until reaching the lock phase by the regulating body (61a, 61 b) engaging sequentially with a plurality of stepped portions (62a to 62d), a first relative rotation is a relative rotation from the most retarded phase or most advanced phase to a first relative rotation phase regulated by a first stepped portion of the n stepped portions (62a to 62d), and a last relative rotation is a relative rotation from an n th -1 relative rotation phase regulated by an n th -1 stepped portion of the n stepped portions (62a to 62d) to a last relative rotation to the lock phase regulated by an n th stepped portion, characterized in that the positional relationship between the stepped portions (62a to 62d) and regulating body (61a, 61b) is set so that, among relative rotations of from the first relative rotation to the last relative rotation, the first relative rotation is configured so as to be the smallest. a drive side rotating member that is adapted to rotate in synchronization with an engine crankshaft; a driven side rotating member, disposed so as to be rotatable relative to the drive side rotating member on the same axis as the drive side rotating member, that is adapted to rotate together with a camshaft that is adapted to open and close at least one of an inlet valve and exhaust valve of the engine; and a locking mechanism that is adapted to lock the relative rotation phase of the drive side rotating member and driven side rotating member at a lock phase, wherein the locking mechanism includes a regulating body (61a, 61b) and n (n is a positive integer) stepped portions (62a to 62d) with which the regulating body (61a, 61b) is adapted to engage, allowing a relative rotation bringing the relative rotation phase nearer to the lock phase and regulating a relative rotation whereby the relative rotation phase is distanced from the lock phase, and the relative rotation phase is regulated in steps from a most retarded phase or most advanced phase until reaching the lock phase by the regulating body (61a, 61 b) engaging sequentially with a plurality of stepped portions (62a to 62d), a first relative rotation is a relative rotation from the most retarded phase or most advanced phase to a first relative rotation phase regulated by a first stepped portion of the n stepped portions (62a to 62d), and a last relative rotation is a relative rotation from an n th -1 relative rotation phase regulated by an n th -1 stepped portion of the n stepped portions (62a to 62d) to a last relative rotation to the lock phase regulated by an n th stepped portion, characterized in that the positional relationship between the stepped portions (62a to 62d) and regulating body (61a, 61b) is set so that, among relative rotations of from the first relative rotation to the last relative rotation, the first relative rotation is configured so as to be the smallest.