The bill will now go before the state's Senate and, if passed, will become law.
Illinois was the scene of a horror road smash late last year in which a double-deck horse truck overturned, trapping 59 draft horses inside.
In all, 19 died from their injuries and the surviving 40 - which animal welfare groups suspected were being trucked to slaughter - were rehomed.
On April 8, the House of Representatives passed the bill by a vote of 80 to 29.
The Animal Welfare Institute praised the vote. Deputy director of government and legal affairs Chris Heyde said: "On behalf of our Illinois supporters and horse lovers around the United States, we commend Representatives Osmond and Molaro and their colleagues in the House for passing this double decker ban.
"The Illinois General Assembly has taken action to stop the brutal injury and death of horses transported on trailers not designed for them. We look forward to seeing the Senate enact this modest and responsible legislation."