The French big-hitters had stormed into a 20-7 lead after 20 minutes in the Welsh capital – despite Rhys Patchell’s first minute try opener.
But a thrilling fight-back saw Josh Navidi (2), Lloyd Williams and Alex Cuthbert as the home side rattled up 27 unanswered points to claim a second European win of the season.
Wilson said: “I am proud of this group of players. For the second week on the bounce we have gone out and really dug in against very good opposition.
“We scored five tries and played some really good attacking rugby. Unfortunately we conceded a little bit and we need to look at that, but I’ve got to be positive after a result like that against a squad like that.
“I just hope that starts to build even more confidence and momentum for us.”
Wilson admitted the turning point of the game had been a try from Josh Navidi in first half stoppage time as Cardiff Blues turned down the kick to go for a driven lineout.
“We backed ourselves going to the corner, we have done it a few times recently, a fair play to the boys that we scored,” he said.
“We felt their drive might be a little bit ill-disciplined so we had to stay tight and disciplined. We did that and we got it right.
“It was a very important time to score to give us that half-time opportunity to tactically make some adjustments and it worked well for us.
“We told the team at half-time that we felt the attacking shape was working well, bringing the likes of Rhys Patchell, Tom James and Alex Cuthbert into the game.
“We had gone away from the kicking game we wanted in the first half; it was feeding the opposition so we decided to play a lot more rugby from deeper.
“It is dangerous and risky, especially if you get turned over in the wrong place, but we felt our attacking game was causing them problems.
“In the second half the majority of the time we kept the ball well and played some good stuff.
“If you feed Montpellier they have got so many gifted strike runners across the field you can struggle to contain them.
“We had that bit of belief too,” he added. “We said at half-time we needed a big first 20 minutes after the break and then to believe in what we are capable of. We did just that.”