Balotelli, who made his first start in six matches against Wigan at the DW Stadium on Wednesday, endured a largely frustrating night but remained focused and gave City the lead with a 69th-minute strike. James Milner added the second three minutes later with a stunning effort to seal the 2-0 win for Roberto Mancini's side.
"Any striker's first league goal is going to be massive in a season. To be fair to Mario, he has not had loads of chances," Barry said.
"When you do get them, you need to score them. He has taken a chance with his start here. It could be good for Mario. Hopefully he can go on a run now.
"Mario is not going to lack in confidence if he misses two or three. He'll keep trying the same things.
"Hopefully his goal will give him a bit more confidence and he can improve from there."
Balotelli was dropped for the match against Tottenham earlier this month and was then kept out by a back injury. Speculation that the 22-year-old will leave Man City during January's transfer window has continued despite Mancini's denials that he is not looking to move him on. Barry believes Balotelli wants to stay at the Etihad Stadium and hopes the controversial striker will quickly start to add to his goal tally.
"I think he is happy," Barry said.
"If you see him day to day then you'd see no reason for him not to be.
"Obviously he has probably not played as much as he would have liked but he has kept his head as well as anyone else who isn't getting chances.
"He scored some massive goals last season and if he can repeat that this season it'll be good for us."
Barry is relieved that City are back to winning ways after successive draws against Chelsea and Real Madrid, although Wigan caused City plenty of problems and missed several chances to take the lead.
"I think at half-time we knew we had to step it up to get any sort of result," the midfielder said.
"The pitch made it quite tough, it was really heavy. Some of the passes in the first half went astray easily. We stepped it up a bit in the second half and deserved the win in the end.
"We looked solid in defence but didn't create too much. It is always important to get that first goal and it came at the right time."