Defenders Steve Metcalf and Danny Dudley, and forwards Chris Smith and Eddie Dsane will return to The Camping World Community Stadium for the 2021-22 campaign.
Metcalf, who is currently the Hornets' longest-serving player, has agreed to stay for his sixth consecutive season at the club.
Dudley will return for another campaign after joining from Isthmian Premier Division rivals Carshalton Athletic late last year.
Smith has signed on for a third season with the Hornets. The striker has netted more than 20 goals over the last two curtailed campaign.
Dsane joined Horsham from National League South outfit Hampton & Richmond Borough last summer, and will look to bounce back after an injury-plagued 2020-21 season.
The Hornets have already confirmed the return of captain Jack Brivio, club legend Gary Charman, Rob O'Toole, Will Miles, Harvey Sparks, Charlie Harris, Tom Day and Doug Tuck.
Horsham have also confirmed that two players have left the club.
Goalkeeper Brad House has returned to parent club Sutton United, while defender Jerry O'Sullivan has joined Tonbridge Angels.