Vandals caused damage estimated at £200 when they smashed two windows at Chorley Little Theatre.
Chorley Amateur Dramatic Society (CADOS), which runs the Dole Lane venue, say they can ill afford the extra expense as they pay for a major refurbishment of the building.
Ian Robinson, chairman of CADOS, said: “It’s obviously very annoying and frustrating. We keep putting a lot of effort in the building and making it look nice and this is just sickening.
“So far we have spent £120,000 which is all our own money. We raised it by ticket and bar sales, as we don’t get any funding. The roof also needs finishing but the windows being smashed is another job we didn’t need.”
He added: “It has happened overnight (on Sunday). Possibly someone coming back from drinking in town with nothing else better to do.
“Unfortunately the CCTV cameras couldn’t see who was responsible.
“The damage will cost around £200 which doesn’t seem a lot but being the fourth time that damage has occurred it all adds up.
“I’m just glad it didn’t happen when we had a show on, the broken glass could of really injured someone.”