Cllr Gwynfor Owen was approached by residents concerned with speeding along the A496 in the town.
He believes action must be taken to clamp down on the issue before tragedy strikes.
He said: “A number of residents at Lower Harlech raised the problem of speeding along the A496, the stretch of road which enters Harlech up to the railway crossing especially at peak times of the day.
“I have visited the site several times and am completely in agreement - this is a huge problem.
“I have discussed the matter with the local police inspector who was very sympathetic and has agreed to try to help catch some of the culprits. The problem however does not lie with catching those responsible, but in stopping the problem from occurring in the first place.
“I am pressing the council for urgent action to be taken. Something needs to be done before we have fatalities, not because of fatalities.
Cllr Owen has asked Gwynedd’s highways officer to accompany him on a site visit.
“The council has agreed to careful monitoring of the area, before deciding what, if any measures are put in place,” Cllr Owen said.
“This will hopefully highlight how much of a problem exists, and enable them to look at different specific measures with the intention of slowing traffic.
“I am glad the council is taking the problem seriously. There have been fatalities in the area in the past and we don’t want to see any more.”
Resident Ann Edwards said: “There are four housing estates with entrances to the main road, the Ardudwy health centre and Ysgol Ardudwy. Also children cross the road from Ty Canol estate to walk along the lane to Ysgol Tanycastell.
“We wrote to Gwynedd Council for a flashing 30 sign many years ago but it was refused. If somewhere needs one Morfa Harlech does.
Harlech Community Council said they had been lobbying Gwynedd Council for many years to get something done.
Gwynedd Council said: “Arrangements are being made for speed counting equipment to be placed at the location. An officer from the traffic service will contact Cllr Owen to discuss the results of the speed survey and arrange a site meeting in order to suggest ways of improving road safety in the area.”