In the play, a power-hungry general kills the King of Scotland to take the throne for himself.
"The committee agreed that the film 'Shakespeare Must Die' contains material causing disunity in the country," the culture ministry's office of film and video said in a statement released Tuesday.
The Thai production was part-funded by the culture ministry.
The royal family is an extremely sensitive subject in Thailand, where 84-year-old King Bhumibol Adulyadej is revered by many as a demi-god.
Thailand has seen as series of sometimes violent street protests in recent years by rival political factions, including the royalist "Yellow Shirts".
Bhumibol came to the throne aged 18 when his brother was shot dead in mysterious circumstances.