Two bus lanes in Fishergate will be enforced 24/7 from Monday.
Cameras will monitor the bus lane running up Fishergate Hill, past County Hall, and down Fishergate, past Boots and Marks and Spencer, issuing penalty notices for motorists who use them.
Lancashire County Council says the aim of the enforcement is t help public transport by ensuring the bus lanes are kept clear.
The bus lane past Boots is currently operational during business hours, but the enforcement will now be in place around the clock.
From 16 December drivers could receive a £60 penalty if they use a bus lane on Fishergate Hill from the junction with Strand Road, past County Hall and the Railway Station towards the junction with Corporation Street.
A bus lane on Fishergate which runs in front of Boots, from Glover’s Court to Cannon Street, will also be enforced from Monday.
There will be an initial period during which motorists will be given warning notices before fines are issued, to give people chance to adapt to the new rules.
County Councillor Keith Iddon, Cabinet member for highways and transport, said: “Bus lanes are an important part of the city centre, as they help people to get around using public transport and help to reduce traffic, making it a nicer place for everyone while they’re here.
“There are lots of other routes for people to use around the city centre, so people shouldn’t be choosing to misuse these bus lanes.
“These PCNs help to discourage this misuse and help buses to get around. We’re happy if we don’t make a penny from the bus lanes, as it means that people are doing the right thing.”
Additional signage has already been put in place, ahead of the start of enforcement.
Both bus lanes can be used by buses and cycles. Hackney Carriages also able to use the bus lane on Fishergate, but not the one on Fishergate Hill.
The standard Penalty Charge Notice (PCN) is £60, which is reduced to £30 if paid within 14 days.