In a news conference, McAllister announced his decision to try to retain the 5th District seat he won in a special election in November.
"We spent the weekend trying to make sure this was exactly right for us and the family," McAllister said.
The first-term Republican's career in politics seemed be at an end earlier this spring when he was caught kissing a married aide on camera. In the days after the tape, which was filmed in December, was made public, McAllister's office fired the aide and McAllister said he would complete his term but not run again.
Later, he said he had the right to change his mind, which he has now apparently done.
"Without a doubt this decision comes after much thought and prayer," McAllister said in a statement. "This district has been home to me and my family all of my life."
"I know the needs of this congressional district very well," he continued. "I also know that this district needs a strong, conservative voice in Congress. I plan to continue to stand up for our veterans, bring common sense solutions to our nation's problems and most importantly I will fight to get our fiscal house back in order."
McAllister swept to victory last year on a platform of family values and with the public support of Duck Dynasty cast member Willie Robertson.
Among those who have announced intent to run for the seat is Zach Dasher, the nephew of Dynasty patriarch Phil Robertson. The Robertsons have endorsed Dasher, a blow to McAllister's re-election hopes.