The United Nations Environment Program (UNEP) said Algeria stopped selling leaded gasoline in July, making it the last country to end its sale and marking an "official end" of leaded gasoline use in cars.
Wealthy countries began phasing out leaded gasoline in the 1970s and 1980s due to health and environmental concerns, but some countries continued to sell it.
UNEP began a final push to ban leaded gasoline in 2002.
"The successful enforcement of the ban on leaded petrol is a huge milestone for global health and our environment," UNEP Executive Director Inger Andersen said in a statement.
Lead was first added to gas nearly 100 years ago, ostensibly to improve engine performance.
Leaded gas is still used on some small airplanes, according to The Associated Press.
Some information in this report comes from The Associated Press and Agence France-Presse.