A quick-release device includes a tube having multiple holes defined through the wall in the first end thereof, and a seat is connected to the second end of the tube. A sleeve is located in the first end of the tube. Multiple stop members are located in the tube and movably engaged with the holes respectively. Each stop member has an inclined face defined in the underside thereof. A lever includes a cam portion pivotably mounted to the first end of an axle which extends through the tube. An end member is movably connected to the first end of the tube and is secured to the second end of the axle. When pivoting the lever, the end member is moved toward the seat or moved away from the seat to be the secure status or the release status.