The City of Perth council has voted unanimously in favour of making the city's three major pedestrian areas smoke-free.
Under proposed amendments to a local law, smoking will be banned in the Hay and Murray Street malls and Forrest Place.
Lord Mayor Lisa Scaffidi said council and city staff had received complaints about harmful second-hand tobacco smoke and the council wanted to ensure a safe and enjoyable environment in high-density pedestrian areas.
"Smokers are very much in the minority these days and there is no reason why we should pander to the minority in health matters such as this," Ms Scaffidi said.
It will take about six months to amend the law and make the necessary arrangements.
In that time the city will conduct a community awareness program and no fines will be issued.
A City of Perth spokesman said the amount of the fine had not yet been determined.
In 2009, the City of Perth banned smoking in all outdoor dining areas, although liquor-licensed premises that did not have a restaurant licence were able to allocate a smoking zone of up to 50 per cent of their outdoor eating areas, provided this was not already deemed an enclosed public place.
It also banned smoking within 10 metres of children's playground equipment and between the flags at patrolled beaches.
Brisbane City Council implemented a smoking ban in Queen Street Mall in 2011 and the City of Adelaide is currently undergoing a six month smoke-free trial in Rundle Street Mall and adjoining laneways.