The award caps an outstanding month for the flying Welshman.
Gareth scored one of the goals of the season, let alone the month, in our agonising 3-2 defeat at Manchester City on January 22 when he hit as first-time curler from 25 yards over Joe Hart and into the top corner.
He then scored twice in Tuesday's 3-1 win against Wigan at the Lane.
"It's always nice for it to be recognised when you've been playing well," said Gareth.
"The team has been playing well and I'm just happy to be playing my part in that."
It's the second time Gareth has won the prestigious award after being named Barclays Player of the Month in April, 2010.
January's award for Gareth follows a club double when Harry Redknapp and Scott Parker won the Barclays Manager and Player of the Month respectively in November.
Gareth was also named in the UEFA.com users Team of the Year for 2011 last month.