Mark Smith has been named as Force India's new technical director.
A media statement said James Key has left the Silverstone based team "to pursue new opportunities".
Smith, who has previously worked with Renault and Red Bull, was already Force India's design director.
Key has been with the team, initially as Jordan, since 1998 as a data engineer.
"We wish him every success in his future endeavours," said team owner and boss Vijay Mallya.
Key confirmed that the move was his decision.
"I felt the time was right for me to move on to new opportunities," he said.
