The British number two was playing his first match since retiring during his third-round clash against Denis Shapovalov at the US Open with a back problem.
Edmund was particularly dominant on first serve in his 6-4 6-2 win against Australia's Tomic, winning 23 of 25 points and hitting nine aces.
Edmund loses to Donaldson in Chengdu
In the second round in China, sixth seed Edmund will face 20-year-old American Jared Donaldson.
Rublev and Zverev wrap up Laver Cup win for Team Europe
Raducanu says she is far from favourite as she commits to Australian Open despite restrictions