Kellock has been out for three months with an arm injury, while Maitland was injured in Scotland's opening game of the RBS 6 Nations against Ireland at the start of February and both have been named among the replacements.
It is the same back three which started in the narrow defeat to Leinster in Dublin three weeks ago, with Peter Murchie continuing at full-back, Tommy Seymour on the right wing and Niko Matawalu occupying the left wing berth.
Alex Dunbar returns from Scotland duty at centre and links up for the first time with Richie Vernon, who scored a brace of tries against Leinster last time out.
After starting all five of Scotland's RBS 6 Nations games, Duncan Weir returns at fly-half, with Cusiter named at scrum-half.
Gordon Reid keeps his place at loose head, while Dougie Hall comes in for Pat MacArthur at hooker and Jon Welsh replaces Ed Kalman at tight head.
It is the same second-row which started at the RDS with Tim Swinson and Jonny Gray once again linking up in the engine room.
In the backrow Chris Fusaro returns at openside, Rob Harley is at blindside and Josh Strauss continues at number 8.
The Warriors beat Scarlets 17-12 at Parc y Scarlets in October and are going for a first season's double over the Welshmen since season 2009/10. Scarlets have won on two of their last three visits to Glasgow.
Glasgow Warriors head coach Gregor Townsend said: "We're looking forward to our first game at Scotstoun in six weeks. This is a really important period of the season and it's great that six of our last eight games will be in front of our home support."
"Scarlets are a quality side, who finished in the top four last season and are only seven points and one place behind us in sixth, so they pose a huge threat."
"Although we won down in Wales in October, they beat us home and away last season, so they know what it's like to win at Scotstoun."
"It's great for us to be able to welcome back a number of Scotland players, but we haven't made a lot of changes to the team which narrowly lost to Leinster earlier this month."
"I was pleased with our performance that night and although we didn't get the result we wanted we came very close to beating one of the best sides in Europe."
"It's been a frustrating few months for Al (Kellock) but he's worked really hard to come back and we're delighted to have him involved again. It's also a bonus that Sean (Maitland) has recovered from injury after missing the majority of Scotland's RBS 6 Nations campaign."
Tickets for Glasgow Warriors v Scarlets at Scotstoun Stadium tomorrow (kick-off 6.30pm) are available from www.glasgowwarriors.org and from the ticket office at Scotstoun Stadium from 10.30am on Saturday right up until kick-off.
Glasgow Warriors team to play Scarlets, RaboDirect PRO12, Scotstoun Stadium, Saturday 22 March (kick-off 6.30pm) - live on BBC ALBA:
15. Peter Murchie
14. Tommy Seymour
13. Richie Vernon
12. Alex Dunbar
11. Niko Matawalu
10. Duncan Weir
9. Chris Cusiter (Captain)
1. Gordon Reid
2. Dougie Hall
3. Jon Welsh
4. Tim Swinson
5. Jonny Gray
6. Rob Harley
7. Chris Fusaro
8. Josh Strauss
16. Fraser Brown
17. Jerry Yanuyanutawa
18. Moray Low
19. Al Kellock
20. Leone Nakarawa
21. Ruaridh Jackson
22. Mark Bennett
23. Sean Maitland
Not available due to injury: Mike Cusack (medical/illness), Ed Kalman (back), Sean Lamont (knee), Tom Ryder (knees) and DTH van der Merwe (shoulder).