Willse, who has been at the paper since 1995, led the daily to its only two Pulitzer Prizes. He also oversaw the difficult cutbacks in staff during last year's buyouts that included a loss of one-third of the newsroom.
Managing Editor Kevin Whitmer will succeed Willse as editor.
Willse, who had held high-level posts at the Daily News in New York and The San Francisco Examiner, was credited with taking the daily to its highest levels as a regional news outlet. But a year ago, he had to oversee its most devastating staff cutbacks as some 200 buyouts were taken, shrinking the newsroom staff by about one-third.
"It's been a terrific run," Willse told the staff at a meeting, the story said. "It has been a great privilege to edit this paper and work with this staff. It's also been an incredible amount of fun."
Before joining the Star-Ledger, Willse worked on Internet projects for Advance Newspapers, the paper's parent company. He succeeded Mort Pye, who had been editor since 1957.
"Jim inherited a great newspaper from Mort Pye and was a worthy successor," Donald Newhouse, president of Advance Publications, said in a story on the Star-Ledger's site. "With a sure touch he served our readers, New Jersey, his staff and the profession brilliantly and with dedication. And he gave me two of the most thrilling days of the 40-plus years I spent at the Star-Ledger -- when the newspaper was awarded its two Pulitzer Prizes.
"As might be expected from such a consummate professional, he has nurtured a successor who mirrors his ethics, energy and values," Newhouse added in the story. "But no one can quite fill the void that Jim leaves. He is my friend and associate and I will greatly miss not having him at the helm."
Whitmer has been at the paper since 1996 and, before becoming managing editor, served as sports editor and oversaw financial coverage and the Sunday paper.
Whitmer, 42, attended Rutgers University. He got his start in journalism as a part-time clerk answering phones in the sports department at The Courier-News in Bridgewater, N.J.
"I am a product of New Jersey, so the thought of editing this newspaper is humbling and more than a little overwhelming," Whitmer said in the story. "But I couldn't ask for a better group of people in the newsroom to share in this fantastic responsibility. They're talented, spirited and fiercely dedicated. And I think I speak for everyone, when I say we couldn't have had a better mentor or friend than Jim."
Willse, 65, began his career with The Associated Press in New York and San Francisco, and served as city editor and managing editor of The San Francisco Examiner before to returning to New York and the Daily News in 1985.
He plans to travel for a few months before becoming a visiting professor at Princeton University, where he will conduct a seminar on the business of news.
By: Joe Strupp Jim Willse, editor of The Star-Ledger in Newark, N.J., announced Monday that he is retiring after 14 years in the position. Willse told the staff Monday he plans to leave in about a month, then teach at Princeton University.