The California Republican made the announcement on Wednesday.
"I have chosen to leave Congress at the end of this term. I take the unusual step of announcing this from the floor of Congress for two reasons. First, this is where my fellow Californians sent me to represent them. Second, I am a proud institutionalist, and I believe that this institution is as great as it has ever been," said Dreier.
Dreier said he had considered leaving three years ago but chose to return to focus on cutting spending, getting free trade bills passed and enhancing national security.
Dreier represents the 26th District, which spans the foothill communities at the base of the San Gabriel Mountains.
Redistricting in the state has made races tough for several incumbents. Three other longtime Republicans - Jerry Lewis, Wally Herger and Elton Gallegly - have announced plans to retire.
In all, 21 Democrats and 16 Republicans in the House have announced that they will not seek reelection.
The Associated Press contributed to this story.
