Plymouth City Council will borrow nearly £290,000 to pay for repairs to the city's Theatre Royal.
The council, which is the landlord of the building, said the venue needs work to stop water getting through the fly tower and smoke vent roofs, with the costs funded through corporate borrowing.
Chris Penberthy, the council's Cabinet Member for Housing, Cooperative Development and Communities, said the theatre was "a cultural powerhouse" that must be kept in good condition.
He said, " As landlords for this important and listed building, we accept that we need to invest in it from time to time to ensure its fit-for-purpose for years to come.
"This building and its staff play a key role in our nighttime economy, in educating and inspiring all ages and in the city’s reputation regionally and nationally."