The left-back, who was named the Supporters’ and Overall Player of the Year for last season, confirmed the news on social media.
Brown was signed by Paul Cox early on in the campaign following his departure from King’s Lynn Town and went on to become one of the most consistent performers during an encouraging season as the Poppies just missed out on a play-off place in the Vanarama National League North.
However, he will not be at Latimer Park next season as a new era for the Poppies gets under way with Lee Glover being installed as manager last week following the departure of previous boss Ian Culverhouse.
Writing on Twitter, Brown said: “My time at @KTFCOfficial has come to an end.
"What a season it has been, relegation favourites to play-off challengers.
"Thank you to all at the club and the fans for making me feel so welcome from day 1, looking forward to what the next chapter holds.”
Brown becomes the third departure so far from Latimer Park this summer after goalkeeper Rhys Davies revealed he has left the club while young striker Isaac Stones has signed for Loughborough Dynamo.
George Cooper and Jackson Smith both returned to parent clubs Mansfield Town and Wolverhampton Wanderers at the end of the season following loan spells at Kettering.