Brown, now 31, said: "There is a special feeling about coming back. My dad retires at Christmas and could soon be going home to Antigua, so this is a good time to be coming back to the Granby Halls.
"I know the place will be buzzing and there'll be pressure on me to make a difference, but I'm confident I can get the job done and help their season."
Brown left the Riders to join Guildford Kings and then moved on to London's two great rivals, the Leopards and the Towers. He won play-off, League Trophy and National Cup titles and also played 51 times for England and made 27 appearances for Great Britain.
Brown began this season with Gorizia in Italy but they struggled to adjust to promotion to Serie A and he left for financial reasons. He makes his second Riders debut tonight at home to Newcastle Eagles.
Worthing Bears' new coach is the British-Canadian Sean Loucks. He replaces Chris Pullem, who walked out on Monday.Reuse content