An adjustable storage seat for recreation and utility vehicles is disclosed. The adjustable storage seat may be used for snowmobiles, watercraft, all-terrain vehicles, or other similar small vehicle intended for entertainment and transportation. The adjustable storage seat comprises a cushion mounted over a frame which is attached to the chassis of the vehicle. The seat is provided with an adjustable backrest which can be adjusted forward or backward in increments to increase the comfort of the rider when a button on the seat is pushed, but otherwise remains fixed in place. The adjustable backrest can also be removed from the seat to reveal a storage compartment after turning it 90 degrees. The seat may be provided with a lock to secure the storage compartment. Additional embodiments of the adjustable storage seat are convertible for one or two person use, and may be provided with internal storage or item racks.