Jeff Bezos, 54, is the world's richest person, with a fortune that has soared to more than US$160 billion thanks to his stake in Amazon, which again became Wall Street's most valuable company this week, surpassing Microsoft.
The couple decided to divorce after a long period of "loving exploration" and trial separation, and expect to continue as partners in joint ventures and projects, according to the statement.
MacKenzie Bezos, 48, is an author who grew up in San Francisco, according to a 2013 profile in Vogue magazine. She attended Princeton University and met her husband when interviewing for a job at a New York hedge fund, according to the magazine. The pair have four children.
At a Business Insider event in Berlin last April, Jeff Bezos said MacKenzie's support was instrumental when he founded Amazon as an online bookseller in 1994, and that she did the accounting for the company in its first year.
"When you have loving and supportive people in your life, like Ms MacKenzie, my parents, my grandfather, my grandmother, you end up being able to take risks," he said at the event.
Mr Bezos in September committed US$2 billion to helping homeless families and starting pre-schools for low-income communities. He had solicited ideas on Twitter in 2017 for ways to donate some of his wealth.
In 2012, the couple donated US$2.5 million to a Washington state campaign to legalise same-sex nuptials there.
From modest beginnings as an online bookseller, Mr Bezos and Amazon branched out into almost every product category available, ending up taking on established retail giants such as Wal-Mart.
Under Mr Bezos, Amazon launched the Kindle e-reader and revolutionized the way books are distributed and read. The company has also been a pioneer in cloud computing.
In November, Amazon picked America's financial and political capitals for massive new offices, branching out from its home base in Seattle with plans to create more than 25,000 jobs in both New York City and an area just outside Washington, DC.