The world number four showed no signs of the shoulder injury which has kept her off court since the Western and Southern Open in August as she raced into the second round in 64 minutes on Pat Rafter arena.
"I was pretty sick of the off-season and I was ready to get going," a beaming Sharapova said on court.
"I missed the game, I wanted to come out here and really perform well and I tried to do that."
Clearly frustrated after so long without any competitive action, the 26-year-old Russian came out firing on all cylinders and raced to a 3-0 lead against her 74th ranked opponent.
The four-times major champion, watched by her new coach Sven Groeneveld, ruthlessly dismantled the big serve that has created excitement around the 20-year-old Garcia.
Sharapova wrapped up the first set with a blistering forehand winner after 39 minutes and two further service breaks later was 4-0 up in the second.
With the momentum all on her side of the court and Garcia shaking her head at the quality of some of the returns coming back over the net, Sharapova grabbed another break and sealed the victory on her own serve with a forearm smash.
The Russian, forced to pulled out of the Brisbane tournament by injury for the last two years, was delighted to finally show off her skills to the Queensland public.
"It's been so long, I'm sorry," she said. "I've been meaning to play this event for so many years and I'm so happy it was this year after being away from the game for a few months."
The third seed will undoubtedly have the majority of the crowd against her in her second round match when she plays Australian teenager Ash Barty, who earlier beat Daniela Hantuchova 6-3 7-5.
"It's going to be another tough one, she's already played four times here which is a huge advantage coming into the new year," said Sharapova, who is seeded to meet world number one Serena Williams in the semi-finals.
German fifth seed Angelique Kerber, the beaten finallist at Wimbledon this year, also beat a French 20-year-old in her first match, seeing off Kristina Mladenovic 6-2 6-2.