According to his agent, John S. Kelly, Nielsen died just after 5:30 p.m. Sunday from complications of pneumonia at a hospital near his home in Ft. Lauderdale, Fla.
Kelly said the actor was surrounded by his wife Barbaree and friends.
"We are saddened by the passing of beloved actor Leslie Nielsen, probably best remembered as Lt. Frank Drebin in 'The Naked Gun' series of pictures, but who enjoyed a more than 60-year career in motion pictures and television," Kelly said in a statement.
"He was having trouble breathing and so they went into the hospital and he just didn't recover," said Nielsen's nephew, Doug Nielsen.
Nielsen was first known as a serious actor but later took on comedy roles, such as Dr. Rumack in "Airplane!" and as accident-prone detective Frank Drebin in the "The Naked Gun" series.
Nielsen performed in 150 TV dramas in New York before arriving in Hollywood in the mid 1950s.
"For years, he was a great dramatic actor and then suddenly he became a comedian," actor Dick Van Dyke said. "He was a friend."
Critics argued he was being cast against type when he starred in comedies, but Nielsen disagreed.
"I've always been cast against type before," he said, adding comedy was what he'd really always wanted to do.
Nielsen was born Feb. 11, 1926 in Regina, Saskatchewan.
The Associated Press contributed to this report.