Gary who was appointed on March 1st 2012 will remain as a non-executive director of Southend United, a position that he has held since 2008.
In commenting about his departure Gary said: “The role is more demanding than I first appreciated and I have had to juggle my other responsibilities.
"The Chairman, quite rightly, is very ambitious for the clubs success, as I am, and although Ron originally described the role as 24/7 I perhaps did not appreciate that that is precisely what is required and to balance my other business interests and meet the clubs needs also is simply not practical.
"Nevertheless the Chairman has invited me to remain as a non-executive director which I am very happy to do and look forward to helping him and the rest of the board advance the club, including its move to the new stadium."
The club will now be conducting interviews for a new appointee.