Lautenberg died from complications from viral pneumonia at 4:02 a.m. Monday at New York-Presbyterian Hospital, according to a statement from his office.
"Michelle and I were deeply saddened to learn of the passing of Senator Frank Lautenberg, a proud New Jerseyan who lived America's promise as a citizen, and fought to keep that promise alive as a senator," said President Barack Obama in a statement. "He improved the lives of countless Americans with his commitment to our nation's health and safety, from improving our public transportation to protecting citizens from gun violence to ensuring that members of our military and their families get the care they deserve."
The multimillionaire New Jersey businessman had health problems in recent years, including a bout with the flu that caused him to miss the Senate's Jan. 1, 2013 vote to avoid the fiscal cliff.
The senator's career included being the principal sponsor of a law banning smoking on domestic airline flights and writing landmark drunk driving laws like the nationwide .08 blood-alcohol standard and the 21-year drinking age law.
He initially retired in 2000 after 18 years in the Senate, but he was called out out of retirement in September 2002 as an 11th-hour replacement for Robert Torricelli, Lautenberg's longtime rival, who had abandoned his re-election bid just five weeks before Election Day.
"People don't give a darn about my age," Lautenberg said. "They know I'm vigorous. They know I've got plenty of energy."
Lautenberg is survived by his wife, Bonnie Englebardt Lautenberg, six children and their spouses, and 13 grandchildren.
The Associated Press contributed to this report.