Work has recently been completed to add lanes and traffic lights to the Golden Way roundabout on the A582 in Penwortham.
The work is in preparation for the opening of the Penwortham Bypass onto the roundabout, which is expected to take 22,000 vehicles each day.
But Penwortham County Councillor David Howarth said a key safety feature has been missed, concerning the lack of a guard rail on the pedestrian crossing from Bank Top Road towards Booths in Millbrook Way.
He said: “The crossing here is over three lanes of traffic and there isn’t a guard rail.
“I’ve spoken to LCC Highways and they say there’s no plans for one because there’s a stretch of grass by the crossing.
“But if you get a boy racer on that roundabout and the sequence of the lights is right, then you can tank up the A582. If you lose it round there, there’s nothing for the pedestrians. Residents are worried.”
A spokesman for Lancashire County Council said: “The purpose of pedestrian guardrails is to prevent pedestrians from crossing where it would not be safe to cross, and guide them towards the formal crossing points which have been provided. They are not designed to act as a safety barrier to protect pedestrians from vehicles.”