Reece Myles-Meekums gave the visitors a half-time lead before Rhys Murphy sealed the Hornets’ first league win in four in second half stoppage time.
It leaves Horsham sixth in the National League South table, while the Sports remain third-from-bottom.
The Hornets visit Leatherhead in the FA Trophy fourth round this Saturday before making the short trip to Three Bridges in the Sussex Transport Senior Cup quarter-finals on Tuesday evening.
Borough, meanwhile, are without a game this weekend but travel to Horsham YM for a Senior Cup quarter-final clash on Tuesday.
See John Lines’ pictures from Eastbourne Borough v Horsham on this page and the ones linked.
1. Horsham FC return to winning ways at Sussex rivals Eastbourne Borough - the match in pictures
Horsham FC returned to winning ways in the National League South with a 2-0 success at Sussex rivals Eastbourne Borough. Photo: John Lines
2. Horsham FC return to winning ways at Sussex rivals Eastbourne Borough - the match in pictures
Horsham FC returned to winning ways in the National League South with a 2-0 win at Sussex rivals Eastbourne Borough. Photo: John Lines
3. Horsham FC return to winning ways at Sussex rivals Eastbourne Borough - the match in pictures
Horsham FC returned to winning ways in the National League South with a 2-0 win at Sussex rivals Eastbourne Borough. Photo: John Lines
4. Horsham FC return to winning ways at Sussex rivals Eastbourne Borough - the match in pictures
Horsham FC returned to winning ways in the National League South with a 2-0 win at Sussex rivals Eastbourne Borough. Photo: John Lines