Langrick Bridge will close from 6pm on Friday night until 6am on Monday morning for ‘waterproofing and resurfacing’ work.
Highways bosses say diversion routes will be signposted.
Richard Waters, principal engineer, said: “We waterproof our county’s bridges to make sure that we protect and extend the lifespan of them. While we do this, we will resurface Langrick Bridge to improve the road surface for motorists.”
A spokesman said local businesses have been informed of the works.