The 49-year-old is rewarded for a successful season that has Leyton Orient sitting top of the National League after 29 matches.
The O’s were sat in 20th position when Edinburgh was appointed last November, following a run of 15 matches without a win, but an excellent second-half saw the E10 side finish in a comfortable 13th position.
Edinburgh’s side have enjoyed a record breaking 2018/19 as they set the Club record for longest unbeaten start to a season while also setting the longest ever unbeaten away run as the O’s have claimed 57 points from 29 matches.
Justin Edinburgh told leytonorient.com, “It was an easy decision for me to sign this extension, there was no second thought, it was just when can we get it done and how long can it be for. I don’t think I have been happier for many a year now.”
Chairman Nigel Travis added, “Justin has demonstrated in the last 13 months what a great leader he is for Leyton Orient Football Club. We are absolutely delighted that he has agreed to extend his stay with us and I believe this will have a very positive impact on the Club as a whole. “