Gloucester scored three tries to run out 23-12 Heineken Cup victors over a lacklustre Edinburgh outfit at Murrayfield on Sunday.
Tries from Rob Cook and Thomas, as well as eight points via the boot of Freddie Burns, gave the Kingsholm-based outfit an 18-5 advantage at half-time.
Greig Tonks' touchdown was the Gunners' response before the interval, but a second try of the afternoon from Gloucester's full-back effectively secured the victory, despite Dave Denton's score.
The visitors have endured a difficult season so far with just two wins from nine Premiership games.
However, a victory over Perpignan in round one of the Heineken Cup at least gave them a platform to potentially build in this competition.
But it was the hosts, who impressively beat Munster in their opening match, that scored first through Tonks' well worked try.
Despite that disappointing start, it was Gloucester that were next on the front foot and Henry Trinder's chip through sent their full-back across the whitewash. Burns' penalty then gave Nigel Davies' men the lead before Twelvetrees and Cook combined to open up a hole for Thomas to scamper through for his first of the day.
Edinburgh currently reside in mid-table in the RaboDirect Pro12 but they were being outplayed by the Premiership's 10th place side, and another Burns' three-pointer took them 18-5 ahead at the break.
Buoyed by their first half display, the Cherry and Whites proceeded to score their third try of the afternoon in the second period when a surging Jonny May run resulted in Thomas going over.
The Scottish side pressed for a way back into the game and Denton crossed the whitewash after 51 minutes to reduce the deficit. But the away team comfortably held out for an impressive win, despite James Hudson's sin-binning.
Tries: Tonks, Denton
Tries: Cook, Thomas 2
Pens: Burns 2
Yellow Card: Hudson
Edinburgh: 15 Greig Tonks, 14 Dougie Fife, 13 Nick De Luca, 12 Ben Atiga, 11 Jack Cuthbert, 10 Harry Leonard, 9 Greig Laidlaw (c), 8 Dave Denton, 7 Ross Rennie, 6 Cornell du Preez, 5 Izak van der Westhuizen, 4 Grant Gilchrist, 3 WP Nel, 2 Ross Ford, 1 Al Dickinson
Replacements: 16 Aleki Lutui, 17 Wicus Blaauw, 18 Geoff Cross, 19 Ollie Atkins, 20 Roddy Grant, 21 Grayson Hart, 22 Joaquin Dominguez, 23 Tom Brown
Gloucester: 15 Rob Cook, 14 Martyn Thomas, 13 Henry Trinder, 12 Billy Twelvetrees (c), 11 Jonny May, 10 Freddie Burns, 9 Jimmy Cowan, 8 Ben Morgan, 7 Matt Kvesic, 6 Sione Kalamafoni, 5 James Hudson, 4 Elliot Stooke, 3 Shaun Knight, 2 Darren Dawidiuk, 1 Yann Thomas
Replacements: 16 Huia Edmonds, 17 Dan Murphy, 18 Rupert Harden, 19 Tom Hicks, 20 Matt Cox, 21 Dan Robson, 22 Mike Tindall, 23 Steph Reynolds
Referee: Jerome Garces (France)