The board releases a mixture of a lactic acid solution that mimics the smell of human sweat and carbon dioxide, which is in human breath.
Its inventors have released the blueprint for free and are encouraging people around the world to make them.
However, one expert warned it could attract insects to areas where there are many humans.
The two companies behind the Mosquito Killer Board, Posterscope and NBS, believe it could help in the fight against the Zika virus, which is carried by mosquitoes.
The insects are drawn to the aroma from the board from a distance of up to 2.5km away, the board's inventors say.
They are then trapped inside it and can be seen in the message it bears, which explains its purpose.
So far, they have installed two of the Mosquito Killer Billboards in Rio de Janeiro, in Brazil.
The firms will not be selling the advertising space inside the billboard.
"It's impressive how many mosquitoes you can trap and how many lives you can save with this idea".
"I think anything that can be done to reduce the prevalence of the mosquito is a good thing".