(Adds analyst comment, context on management changes)
By Lisa Baertlein
LOS ANGELES, Aug 31 (Reuters) - McDonald's Corp on Wednesday said Michael Andres will retire as president of McDonald's USA at the end of the year as the fast-food chain fights to maintain the momentum of its turnaround plan amid intense competition from industry rivals and low grocery prices.
Andres, 58, took the helm of U.S. operations in October 2014, returning to McDonald's after serving as chief executive and chairman of the Logan's Roadhouse Inc restaurant chain.
Andres was appointed by Don Thompson, who was CEO before Steve Easterbrook was elevated to that job in 2015 with the mandate to revitalize McDonald's slumping business.
Andres will be succeeded by Christopher Kempczinski, 47, currently McDonald's executive vice president of strategy, business development and innovation.
Kempczinski came to McDonald's last year from Kraft Foods Group, where he was executive vice president of growth initiatives and president of its international business.
The United States is McDonald's top profit market and analysts said the announcement was unexpected.
"This comes as a surprise," Hedgeye Risk Management analyst Howard Penney said.
"The biggest question becomes the continuity of the turnaround," said Penney, who added that McDonald's has a deep bench of management talent.
Jeff Stratton, who headed McDonald's USA before Andres, was 58 when he retired. He also held the job for about two years.
Shares of McDonald's were up 0.3 percent at $115.66 in extended trading. (Reporting by Lisa Baertlein in Los Angeles; Editing by Jonathan Oatis, Bernard Orr)