The home side have made just one change to the side which beat Sale Sharks, with Seb Jewell pushing winger Phil MacKenzie to the bench.
Mike Tindall has been named in place of Henry Trinder in the Gloucester centres, with the youngster named on the bench.
Sione Kalamafoni is moved to number eight in place of Gloucester's England international Ben Morgan, who is out with a dead calf.
Speaking ahead of the match, Gloucester director of rugby Nigel Davies said: "They're a very strong team, a proud side. They've got a lot of points to prove, individually and collectively, and, if you get it wrong against them, they will beat you."
London Welsh: Jewell, Arscott, Parker, Tonga'uiha, Scott, Ross, Keats, Montanella, Briggs, Ion, Mills, Corker, Browne, Hills, Jackson
Gloucester Rugby: Cook, May, Tindall, Twelvetrees, Simpson-Daniel, Burns, Robson, Wood, Edmonds, Harden, Savage, Hamilton, Buxton, Hazell, Kalamafoni
Sports Mole says: Gloucester