WASHINGTON — Add this to his legacy: President Bush can sing. Well, he can be a good sport about it, anyway.

In a tuxedo and cowboy hat, the president sang his own farewell tune Saturday night at the annual dinner of the Gridiron Club, an invitation-only institution of Washington journalists. On a night of skits and satire, Mr. Bush surprised a high-powered crowd by crooning with the help of backup singers he called the “Busharoos.” The audience — Supreme Court justices, lawmakers, big-name reporters, and more — rose to applaud his effort, the first singing performance by a president at the annual dinner of the club since it was founded in 1885.

To the tune of “Green Green Grass of Home,” Mr. Bush sang about his life ahead — on the ranch, with his dog, and without the meddlesome press around.

“As I step down from the plane and there to meet me is my mama and my papa, down the lane I look and here comes Barney, heart of gold and breath like honey,” Mr. Bush sang.

“Yes, you’re gonna miss me, the way you used to quiz me,” he sang to the reporters. “It’s good to touch the brown brown grass of home.”

Mr. Bush said his singing was the “first and final performance” of its kind. He also told reporters that he appreciated their work, for the most part.

“Now, it’s true you sometimes get on my nerves,” he said. “But when you’re not writing your stories, you’re really not half bad.”

This was Mr. Bush’s last Gridiron Club dinner; his presidency ends on January 20, 2009. Before he left the stage, Mr. Bush made sure that his acquaintances would not be forgotten. He joined other performers and the whole crowd for a send-off rendition of “Auld Lang Syne.”