The RX-77-2 Guncannon was a mobile suit used by the Earth Federation Forces introduced in the TV anime Mobile Suit Gundam.

A middle-range support mobile suit developed simultaneously with the RX-78 Gundam and the RX-75 Guntank as part of Operation V, the Guncannon adopted the same Core Block System as the other two units. Due to its role as an artillery support unit, the Guncannon's design prioritized durability over mobility, and it was not equipped with any melee weapons. However, its armor was particularly heavy, capable of surviving a direct hit from an MS-09R Rick Dom's giant bazooka.

Similar to the Guntank, the Guncannon's main weapons were a pair of shell-firing cannons, chosen for their reliability over beam weapons. These cannons could be optionally swapped out for a pair of spray missile launchers. Unlike the Guntank, however, the Guncannon's generator output allowed it to equip a beam rifle. It was also equipped with a pair of head-mounted Vulcan guns and hand grenades for attacking enemy strongholds.

Though its head design appeared to be simpler than the Gundam's head, the Guncannon's sensor system was in fact more complicated than the Gundam's due to its need to engage in artillery warfare. This "twin eyes with goggles" sensor design were later inherited by the RGM-79 GM. While the Guncannon's mobility was adversely affected by its weight, it was still comparable to that of the Zeon's MS-06 Zaku II. Furthermore, the backpack thrusters have sufficient thrust to enable jumping maneuvers under gravity for a short period of time.