The Bears made it four wins from their last five Blast games, with Mousley scoring 71 from just 36 balls to help set up the victory, which keeps the Bears’ chances of progressing through to the knockout stages alive.
The Bears posted 203 for four in their 20 overs thanks to a 125-run fourth wicket partnership between Mousley and the in-form Beau Webster, before Usman Tariq starred with the ball as Gloucestershire were restricted to 173 for six.
Webster became the first player to reach 500 runs in this year’s Blast by scorching a 44-ball 78 as he registered his fifth score of 50 or more in this year’s competition.
He was joined by Mousley at the crease with the score on 69, after Zen Malik (32 off 19 balls) had got the innings off to a fast start, with Mousley adding 71 off just 36 balls.
It's the second time Webster and Mousley have put on over 120 together in the Blast this season, after they combined to score 145 for the third wicket in the Bears' victory over Somerset in Taunton last month.
Gloucestershire’s innings got off to a fast start with David Malan (30) and D’Arcy Short (25) putting on 58 for the first wicket before Tariq changed the direction of the game.
Tariq dismissed both Malan and Short in the space of two overs, and added a third wicket in a four-over spell that gave up just 12 runs to halt Gloucester’s chase.
After putting together an impressive run of form, Mousley says the team have placed an emphasis on having fun in recent weeks which has allowed them to play with freedom.
“Playing T20 cricket at Edgbaston is great, and it’s a chance to go and have some fun,” he said. “That's something which we're really trying to make an emphasis on, and it's something we speak about a lot in the dressing room.
“It's on our whiteboard; go and have some fun. That's what we've done the last few weeks, and we’ve been winning. We've won four out of five now. The shackles are off and we’re playing some free cricket.
“We feel like we're on a bit of a roll and we just want to keep on performing and seeing where we are. Hopefully we can keep this momentum going.”
Mousley was quick to highlight the impact both overseas players have had, with Webster currently the leading run-scorer in the Blast and Tariq going for just 25 runs in his last eight overs across the last two fixtures.
“Slug [Beau Webster] has been the best batter in the competition,” he added. “Hopefully he’s going to keep coming back to us because I know he loves spending time with the boys.
“We’re very lucky to have him and Usman. Uzzy is a genius. I'm glad I don't have to face him.
“He's a serious operator and we're very lucky to have him too. He's brilliant in the dressing room. We've all got a smile on our face when Uzzy's here and he's been brilliant. To have a world-class operator like him in our team is pretty special.”
The Bears return to action on Friday 10 July, as they entertain Glamorgan at Edgbaston at 7:00pm as part of the final home double-header of the Blast.