Thousands of Queenslanders have been fined over the past 8 years for smoking in their cars with children present.

The Queensland government has reportedly made over $800 000 in fines over the last 8 years, with just over 3600 fines being given, and the on the spot fine costing $252.

Cancer Council Queensland Chief Executive Chris McMillan said the fines are vital to protect children from second-hand smoke in cars, and care should also be taken in the home.