The speed limit through Aireys Inlet has been reduced by 10km/h.
A 50km/h trial along a stretch of the Great Ocean Road was held for six months from December last year, taking in the peak summer period.
The trial found traffic volumes range from 4,000 to 15,000 vehicles each day.
The new speed limit brings the town into line with others along the tourist road.
The Victorian government says it will only add seconds to the overall journey of people travelling through the town, but it reduces the risk of death or serious injury in a crash.