Griezmann left Atletico Madrid for Barca in a €120million deal in the close season, but he has failed to find his best form so far at Camp Nou.
Having played predominantly out wide rather than in the central role he occupies for France and used to fulfill for Atleti, the 28-year-old has four LaLiga goals in 10 appearances this term.
However, Deschamps has no concerns over Griezmann, claiming he simply needs more time to adapt to life at his new club.
"Not at all. Even if you have great players at Barcelona, it doesn't happen in a day. It depends on how they play, how they work with each other," Deschamps told a news conference after again selecting Griezmann for international duty.
"Also, he's put in different positions than the ones he has with France, even though he played [wide] a long time ago.
"He must fit in, the other players as well. He didn't choose the easiest solution and it's a big club, so the expectations are huge. He's always part of a team, but he's not used to it yet.
"Even when he's not as good, he's always positive for the team. With us, it's a different situation, different position, he can play at his best position where I've put him a long time ago. Of course, he has a very important role in how we play."
Another forward who has made the cut for France and has been a pivotal player under Deschamps is Olivier Giroud.
Giroud has made just four Premier League appearances for Chelsea so far this season, with Frank Lampard preferring Tammy Abraham and Michy Batshuayi to the 33-year-old, who has been restricted to 211 minutes of club action across all competitions.
However, the former Arsenal striker remains a key player for France, scoring against Iceland and Turkey in October.
"I picked him last month because of what he did in the past. He's an important player for us. He proves it on the pitch," said Deschamps, who again stressed the importance of Giroud getting more game time.
"When he scores, it's good for him. It happens quite frequently and, even when he doesn't score, he's an important player for us.
"Sadly, the situation hasn't evolved for him, but he is there because I trust him, because of what he has done in the past and in October. Of course, and he knows it, I hope the situation will change with his club for our games in March.
"He needs to play, even though he is very fit, he needs to be more on the pitch."