A jon boat (or johnboat) is a flat-bottomed boat constructed of aluminum, fiberglass, wood, or polyethelene with one, two, or three seats, usually bench type. They are suitable for fishing, hunting and cruising. The nearly flat hull of a jon boat tends to ride over the waves rather than cut through them as a V-hull might; this shallow draft – only a few inches – enables the jon boat to operate in very shallow water, but limits its use to calm waters. Jon boats typically have a transom onto which an outboard motor can be mounted. They are simple and easy to maintain, and inexpensive, though with many options to upgrade. Typical options may include live wells/bait wells, side or center consoles, factory installed decks and floors, electrical wiring, accessory pads/mountings, and casting and poling platforms.

Jon boats are available commercially between 8 and 24 feet (2.4 and 7.3 m) long and 32 to 60 inches (81 to 152 cm) wide, though custom sizes may be found. The simple design includes an open hull, without a bilge, leaving the ribs exposed. Many users choose to cover the ribs, producing a flat, level surface.

The Wasserwacht branch of the German Red Cross has chosen jon boats for their civil protection units for use during floods.