The technical director of the Porsche LMP1 project, Alex Hitzinger, will depart the team at the end of the month.
Hitzinger was one the core architects of the Stuttgart marque's return to top-flight sportscar racing, joining the team in 2011 after five years spent as Head of Advanced Technologies for Red Bull.
The 919 Hybrid made its WEC debut in 2014, becoming the dominant force in sportscar racing last season with six successive race victories, beginning with Porsche's 17th overall win in the Le Mans 24 Hours.
Porsche however has now confirmed Hitzinger will leave the team on 31 March "to take on a new challenge outside motorsport."
"On behalf of Porsche I want to thank Alexander Hitzinger very much for his huge contribution to the outstanding successes of the Porsche 919 Hybrid," said Porsche LMP1 head Fritz Enzinger.
"He was one of the first people to come on board at the end of 2011. I appreciate his desire for a new challenge."
Porsche says it will name Hitzinger's successor at "a later date."