After a trial separation, they have decided to separate, but will continue to share their lives as friends, Bezos tweeted. They have four children.
Read the complete message:
"We want to make people aware of a development in our lives. As our family and close friends know, after a long period of loving exploration and trial separation, we have decided to divorce and continue our shared lives as friends. We feel incredibly lucky to have found each other and deeply grateful for every one of the years we have been married to each other. If we had known we would separate after 25 years, we would do it all again. We've had such a great life together as a married couple, and we also see wonderful futures ahead, as parents, friends, partners in ventures and projects, and as individuals pursuing ventures and adventures. Though the labels might be different, we remain a family, and we remain cherished friends.
Jeff & MacKenzie"
Bezos, 54, and MacKenzie, 48, met and got married while working at D.E. Shaw, a New York-based hedge fund, in the early 90s. Shortly after, they packed up and moved across the country to Seattle, where Bezos launched Amazon.
Bezos is now the world's wealthiest person, with an estimated net worth of $137 billion, according to the Bloomberg Billionaires Index. That means this divorce could end up being very costly.
WATCH: Five facts about Amazon's Jeff Bezos
MacKenzie is an author of multiple novels, including "Traps" and "The Testing of Luther Albright".
Last year, the couple announced plans to commit $2 billion to fund existing nonprofits that help homeless families and also to create a network of preschools in low-income communities.
Amazon is now the most valuable company on the planet
Bezos has been the wealthiest person on the planet for more than a year. Now, Amazon is the most valuable company in the world.
It passed Microsoft (MSFT) Monday to take over the top spot. Amazon's stock rallied another 1% Tuesday and the company is now worth nearly $810 billion, compared to about $790 billion for Microsoft.
Amazon is up 10% already this year. Bezos has 16% ownership stake in Amazon. Bezos also owns space exploration company Blue Origin and The Washington Post. Bezos has a more-than-$40-billion lead over the world's second richest person, Microsoft cofounder Bill Gates.
Still, Amazon's rise to the top of the world's most valuable rankings doesn't mean that Amazon is trading at its highest price ever. The company briefly topped the trillion-dollar mark last September.
But Amazon (AMZN) and other tech stocks have all tumbled from their peaks in the past few months along with the broader market. Amazon's shares are still nearly 20% below their record high.
The market has taken a big bite out of Apple
Apple has fallen even further. Not too long ago, Apple was the most valuable company on Earth with a market cap that peaked above $1.1 trillion. It's down more than 35% from its all-time high.
Investors have punished Apple (AAPL) because of slowing demand for smartphones. The company's stock plunged last week when it warned its iPhone sales would be lower than forecast for its most recent quarter, largely because of weakness in China.
The company's market cap is now $710 billion. It's fallen to fourth place behind Amazon, Microsoft and Google owner Alphabet (GOOGL), which has a market value of about $750 billion.
CNN contributed to this report.