The rioters on Sunday slightly injured two Bangladeshi civilians, who happened to be visiting the embassy, Bangladeshi Ambassador Nazrul Islam Khan said.
The embassy called the police, who evicted the workers and arrested some of them, while the other rioters fled, Khan added.
The local police commander declined to answer any questions, but suggested that the media contact the Interior Ministry's spokesman, who was not immediately available.
Journalists who entered the embassy, shortly after the police intervened, saw chandeliers had been ripped off the ceiling, chairs and tables had been smashed, official papers scattered across the floor and framed tourism posters yanked off the walls.
The door to the ambassador's office had been forced, but the office appeared to be unharmed.
There was no immediate word on the motive, but it was suspected the violence was sparked by non-payment of the workers' salaries - a frequent complaint in Kuwait.
Gulf's construction projects rely
heavily on South Asian labour
Khan said he did not know why the labourers had attacked the embassy, but he said he was sure they were people ''who were suffering".
However, other reports claimed that the workers were demanding that the embassy intervene to ensure they receive their salaries.
He said Bangladeshi workers regularly came to the embassy to complain about their employers' failure to pay them, but ''this time nobody came to discuss it".
He said the protest must have been organised because the workers arrived in buses. After their arrival, the workers threw rocks at the embassy windows.
They overpowered the guards and entered the embassy. They also smashed the windows of five cars parked outside the embassy.