After an uneventful first half, the hosts took the lead in the 55th minute when Nathan Blissett poked in Dan Sparkes' cross and they had a two-goal cushion 10 minutes later after David Fitzpatrick slid the ball home.
It appeared as if Torquay had wrapped up the three points on 69 minutes when Sean McGinty found the net with a header but they were stunned by three Forest Green goals in four minutes.
Substitute Christian Doidge's header gave the visitors a lifeline in the 73rd minute before Charlie Clough smashed home a second and Ethan Pinnock nodded in an equaliser.
All the momentum was with Forest Green but Ben Gerring's close-range header eight minutes from time gave Torquay a thrilling win.
Report supplied by the Press Association.
Match ends, Torquay United 4, Forest Green Rovers 3.
Second Half ends, Torquay United 4, Forest Green Rovers 3.
Substitution, Torquay United. Joe Ward replaces Dan Sparkes.
Ethan Pinnock (Forest Green Rovers) is shown the yellow card.
Goal!  Torquay United 4, Forest Green Rovers 3. Ben Gerring (Torquay United).
Goal!  Torquay United 3, Forest Green Rovers 3. Ethan Pinnock (Forest Green Rovers).
Goal!  Torquay United 3, Forest Green Rovers 2. Charlie Clough (Forest Green Rovers).
Goal!  Torquay United 3, Forest Green Rovers 1. Christian Doidge (Forest Green Rovers).
Substitution, Forest Green Rovers. Keanu Marsh-Brown replaces Charlie Cooper.
Goal!  Torquay United 3, Forest Green Rovers 0. Sean McGinty (Torquay United).
Goal!  Torquay United 2, Forest Green Rovers 0. David Fitzpatrick (Torquay United).
Substitution, Torquay United. Jamie Reid replaces Sam Chaney.
Substitution, Forest Green Rovers. Elliott Frear replaces Daniel Wishart.
Substitution, Forest Green Rovers. Christian Doidge replaces Drissa Traoré.
Substitution, Torquay United. Paul Rooney replaces Giancarlo Gallifuoco.
Goal!  Torquay United 1, Forest Green Rovers 0. Nathan Blissett (Torquay United).
Second Half begins Torquay United 0, Forest Green Rovers 0.
First Half ends, Torquay United 0, Forest Green Rovers 0.
Shamir Mullings (Forest Green Rovers) is shown the yellow card.
First Half begins.
Lineups are announced and players are warming up.
Torquay shrugged off surrendering a three-goal lead to snatch a 4-3 victory over third-placed Forest Green in the National League.