US pop legend Billy Joel has married longtime girlfriend Alexis Roderick, popping their nuptials on unsuspecting guests at a July 4 holiday party.

The wedding, which took place on Joel’s Long Island estate, was officiated by New York Governor Andrew Cuomo.

• How Jessie J is rescuing The Voice Australia

Joel and Roderick “surprised guests at their annual July 4th party by exchanging vows in front of their family and close friends,” said a statement issued by Joel’s publicist Claire Mercuri on Sunday.

Among the guests were actor Kevin James and Joel’s daughter Alexa Ray Joel – whom he had with his second wife, former supermodel Christie Brinkley.

Joel, 66, and Roderick, who is in her early 30s according to US media, are expecting their first child in the next few months.