A locking structure for a saddle type vehicle to prevent theft and achieve a tamper-proofing effect while securing a storage space in a vehicle body. A front cover is provided with a storage part which is openably closed with a lid. The lid is lockable into a closed state or unlockable from the closed state by means of a lid lock mechanism. A main seat is lockable into an engaged state with seat rails or unlockable from the engaged state by means of a seat lock mechanism. At least one of the lid lock mechanism and the seat lock mechanism is connected to a key cylinder by a first cable and a second cable. The key cylinder overlaps a steering shaft in a side view, and is located within an opening provided in an inner cover, which is a component of the front cover, in a top plan view.