The former Netherlands goalkeeper had just over a year remaining on his previous deal, having held his current role since 2016.
Van Der Sar has been part of the Ajax boardroom for the past ten years, contributing to their immense successes on and off the pitch during these past few years.
Ajax have won the Eredivisie title three times in Van Der Sar's time as CEO and enjoyed a memorable run to the Champions League semi-finals in the 2018/2019 season.
"A lot has happened in the last ten years at Ajax," Van der Sar, who also spent nine years in goal for Ajax, told the club's official website.
"In these years we have grown with the club in many ways. The international recognition has, mostly due to the results of the first team, grown substantially.
"But there is also an amazing organisation behind that success. Our goal is to become a structural part of the international top teams.
"Starting 2024, the design of the European tournaments will change, and we want to compete yearly in the renewed Champions League.
"That journey is not at an end, and I want to keep contributing to that process. Every day I get to work with enthusiastic co-workers who also want to keep raising the bar.
"Not only with the first team, but also in the office, the youth academy, and the Ajax Women.
"The stadium is always packed and the growth in sales of various Ajax kits to young and old, not only national but also international, is unreal.
"We feel the support of our fans home and away. Enough reasons to keep putting my heart and soul in this club the coming years."
Van Der Sar also played for Juventus, Fulham and Manchester United during his playing career, winning four Premier League titles and the 2008 Champions League with the Red Devils.
