Smokers caught lighting up at taxi ranks and bus stops in Sydney could cop a $300 fine as part of a police blitz.

On-the-spot-fines will be given to anyone caught smoking on trains, light rail, buses, ferries and at railway stations, bus stops, ferry wharves, taxi ranks and light-rail stations, police say.

"Police, health inspectors and transport officers [will] deploy together in regular operations at Sydney's busiest public-transport hubs," police said.

The first anti-smoking blitz will target Central Station on Tuesday.

"We'll be concentrating our efforts on the morning and afternoon peaks, and in areas where we know people light up illegally," acting Superintendent Kerrie Lewis from the police transport command said.