The league announced this afternoon that the long-serving man, who had worked 'tirelessly' in his roles for almost 60 years, had died earlier today.
Alan was a true league stalwart having had a long-running affiliation which included periods of being both chairman and secretary during his administration career.
A statement read: "The Isthmian League is very sad to announce that our president, Alan Turvey, died this morning in Basingstoke Hospital.
"Alan had previously been in the Brompton Hospital where he had undergone two operations for a heart problem, and was moved to Basingstoke only yesterday because he had recovered from this surgery."
He has been connected with the league for nearly 60 years, having started as a linesman on the auxiliary list in 1959.
He advanced as a referee through the Isthmian League, eventually officiating in the old Football League Division One and, after retiring as a match official, he became league secretary and then chairman, an office he held for 33 years until he stepped down in 2016. He became league president in 2000.
Bostik League chairman Nick Robinson added: “We have today lost a great Isthmian. Alan worked tirelessly for the league from 1978 when he became a divisional fixture secretary, and he oversaw the development of the league for over 30 years from 1982- during which time the league moved from an amateur league to the fully professional league it is now.
"He will be sadly missed by his many friends in football."
All clubs are being asked to hold one minutes appreciation before each match from tonight until next Saturday.