The plot is set in military hospital during the Korean War - seems like not very good place for sitcom, but you would be surprised. Doctors are busy chasing nurses, nurses are busy avoiding doctors and the commander is trying to avoid being commander.
| | as Benjamin Franklin Pierce
Best surgeon in MASH 4077. He is balanced between being responsible doctor and a prankster. |
| | as Walter O’Reilly
Corporal Radar O’Reilly is short and looks inconspicuous, but in practice he runs MASH 4077 while Henry Blake just signs everything Radar puts in front of him. |
| | as Franklin Marion Burns
Frank Burns has to share the tent with Pierce nad McIntyre (later Hunnicut), but he is the opposite from them - religious, abstainer and devoted by-the-book officer. |
| | as Trapper John McIntyre
Surgeon at 4077th, shares tent with Hawkeye and also his sense of humor. |
| | as Henry Blake
Commander of 4077th, although mostly on paper - he leaves all the important stuff on Radar’s shoulders and just signs everything he is told to. |
| | as Margaret Hot Lips Houlihan
Officer of 4077th and often target of Hawkeye’s and Traper’s jokes. She is in on-off relationship with Frank Burns. |
| | as B.J. Hunnicutt
Surgeon, Traper’s replacement. |
| | as Sherman T. Potter
Commander of 4077th, who took over after Henry Blake left. Very strict, former cavalry officer. |
| | as Maxwell Klinger
The most reluctant soldier in 4077th, Klinger will do anything to get out of army. Literally everything. |
| | as Francis Mulcahy
MASH 4077 chaplain often feels out of place surrounded by doctors and nurses enjoying each others company. |
| | as Charles Winchester
Surgeon, who joined 4077th after Frank Burns left. His stand-offish nature and pompous character irritates Hawkeye every single day. |
| | as General Hammond
General in charge of the mobile hospitals, close friend of Hot Lips. |
| | as General Clayton
General in charge of the mobile hospitals. |
| | as General Mitchell
General in charge of the mobile hospitals. |
| | as Colonel Flagg
Intelligence officer, who maniacally seeks spies. |
| | as Major Sidney Freedman
Psychiatrist, who helps 4077th staff from time to time. Mostly helps them get rid of their money during poker games. |
| | as Ugly John Black |
| | as Ginger Bayliss
Nurse at 4077th. |
| | as Nurse Kellye
Nurse at 4077th. |
| | as Margie Cutler
Nurse at 4077th. |
| | as Sergeant Rizzo
Sergeant in charge of the motor pool. |
| | as Sergeant Zale
Sergeant in 4077th, usually in charge of supplies. |
| | as Ho-Jon
Korean teenager, who helps around The Swamp. |