The Prevention of Equine Cruelty Act, sponsored by Senators Mary Landrieu (D-LA) and John Ensign (R-NV) have the bipartisan support of 14 colleagues who are co-sponsoring the bill.
While state laws closed the last remaining plants in the US, tens of thousands of American horses continue to be trucked to Canada and Mexico for slaughter.
Animal welfare groups have condemned the practice, saying animals are trucks for hundreds of miles, sometimes in double-deck trucks designed for cattles, without food, water or rest.
They have also spoken out against a practice at some Mexican slaughterhouses where horses are stabbed repeatedly in the spine until they are paralyzed, after which they are butchered while still conscious.
Senator Mary Landrieu, a long-time champion of efforts to end US slaughter, said: "America's horses are being beaten and dragged across the border into Mexico and Canada so that they can be inhumanely slaughtered for food.
"I will continue to fight in Congress to end this brutal practice and ensure that American horses will no longer be savagely slaughtered for human consumption," she said.
Senator Ensign said: "The time to put an end to the practice of slaughtering horses in America is long overdue. Horses have an important role in the history of our country, particularly the West, and they deserve our protection. As a senator and a veterinarian, I am committed to doing what I can for these magnificent animals."
The introduction of the legislation comes at a time when several state legislatures are exploring the viability of allowing slaughter plants to be established.
"We have great confidence that the Prevention of Equine Cruelty Act will move quickly," said Chris Heyde, deputy director of legislative and government Affairs for the Animal Welfare Institute.
"The bill, which has had strong support from a majority of Congress and the American public, is long overdue. For years I have pleaded with the pro-horse slaughter camp to stop misleading the public but they are more concerned with wringing a few bucks from a suffering animal than doing what is right."
He commended the senators for introducing the bill.
An identical version, HR 503, was introduced earlier this year in the House of Representatives by House Judiciary Chairman John Conyers, Jr. (D-MI) and Representative Dan Burton (R-IN). There are currently 112 bipartisan cosponsors of the Prevention of Equine Cruelty Act in the House of Representatives.