Stephen Lehec is to leave Aylesbury Grammar School after five years as headmaster.
Mr Lehec handed in his resignation at the school this week and will leave his post in July 2014 to join Kingston Grammar School in the autumn.
He said: “It is with a heavy heart that I have taken the decision to leave Aylesbury Grammar School, but the role of headmaster at Kingston Grammar School is a fantastic opportunity.
“I joined AGS aware of its reputation for excellent students and staff, and over the course of my time here I have come to appreciate that this is an outstanding school.
“I have made many great friends here over the years and I would like to thank the staff, students and parents for all their support.”
Mr Lehec joined the Walton Road school in 2006 as deputy head before becoming headmaster in 2008.
In his letter to parents and students today (Friday), chairman of governors Jim Collins said: “While I am very sad that he has decided to move on, I fully understand his reasons for making the move at this stage of his working career and family life.
“I know that with me you will all wish him the very best for the future.”
He said Mr Lehec has been responsible for a number of successful initiatives while securing the school’s academy status.
His overhauling of the timetable, fostering of closer links with Aylesbury High School and increased engagement with alumni were significant developments for the school, Mr Collins added.
Mr Collins has initiated the process of finding a replacement headmaster with the view of making an appointment in the spring.