Gongmen Jail is a prison located on Black Dragon Alley in Gongmen City, once serving as a kung fu academy to young fighters under the instruction of Masters Thundering Rhino, Storming Ox, and Croc. Once Lord Shen took over the city, however, he had murdered Rhino and arrested Ox and Croc, placing them in this area he organized to be a jail.
Sitting in the middle of the jail is a "fight club" arena where new warriors would once test their skills and strength against one another. After Shen's takeover, this arena was converted into the cell area.
The jail is circular in design and contains two levels: the upper circling balcony where the main entrance is located, and the lower area where the cells are located. Cages of varying sizes hang from the ceiling, dangling high over the cell area. The floor is designed like a yin yang symbol.
After Lord Shen invaded Gongmen City and killed Master Thundering Rhino with his cannon, he forced Storming Ox and Croc to surrender by threatening to turn his weapon on the city. Storming Ox and Croc were imprisoned in Gongmen Jail while Shen took over the city.
Days later, Po and the Furious Five arrived in Gongmen City to stop Shen. After receiving a tip-off from a grateful sheep, the warriors sneaked into the jail in order to free Ox and Croc and enlist their help. However, Ox and Croc had come to believe that kung fu was useless against the weapon, and refused. They resisted Po's attempts to get them out by force, and even when their scuffle destroyed the cell door, they simply walked into the opposite cell and sealed themselves inside. Ox declared that kung fu was dead, shocking Po and the Five, and the angered panda told the two masters to stay in their cell in shame. The warriors were forced to leave Ox and Croc when Boss Wolf and his soldiers discovered them.
Later that night, Po and the Five returned into the jail to hide after a foiled attempt to stop Shen. Tigress confronted Po on the inexplicable distraction he faced in the middle of capturing Shen and demanded an explaination, but When Po refused to answer, she ordered him to remain in the jail, where she said that Master Croc and Storming Ox would "keep [him] far away from danger," while she and the Five would try to defeat Shen at the Fireworks Factory. She ended up fighting Po when the panda insisted on joining them. Po eventually revealed that Shen knew what happened to his lost parents, and said that he needed to learn the truth. Though empathetic, Tigress told Po to stay behind because she couldn't watch her friend be killed, and she left with her comrades. However, Po disobeyed her, ignored Master Ox's statement that he was better off staying where he was, and traveled to the factory afterward.Though not shown, Master Shifu eventually traveled to Gongmen City himself and convinced Ox and Croc to leave their cells and join the battle against Shen.
- Head of story Phil Craven explained how one of the original concepts for this location was instead an underground kung fu training club, disguised to look like a medicine shop (or also a tea house from one of the concept pictures) at the ground level. This came from one of their early story concepts of there being a ban on kung fu in the city.