The flying Welshman was named Young Player and Player of the Year by the Professional Footballers' Association (PFA).
It's only the third time in the 40-year history of the awards that a player has won both prizes following Andy Gray (1976-77, at Villa) and Cristiano Ronaldo (2006-07, at United).
Gareth also became the first Spurs player to lift the PFA Player award on two occasions, after taking the main prize in 2010-11.
"It's a massive honour," said Gareth. "To be voted by your peers is one of the biggest things in the game. It's great to win it and I am delighted.
"When you look at the list there are some massive names on it but I couldn't have done it without the team. They have been fantastic this year and so has the manager.
"I couldn't have won it without them so I would like to give them all a big thank-you as well.
"The other nominees have been unbelievable, they have been outstanding for their clubs and it's a massive moment to win, especially as it's both awards and it's something that I'm extremely proud of."
Gareth has enjoyed a fantastic season so far with 24 goals in all competitions, including 19 in 29 appearances in the Premier League.
Four Spurs players have won the PFA Player of the Year Award - Pat Jennings (1975-76), Clive Allen (1986-87), David Ginola (1998-99) and Gareth (2010-11, 2012-13).
By winning the Young Player award, Gareth also follows in the footsteps of Glenn Hoddle (1979-80) and team-mate Kyle Walker, who won it last year.