Federer, aiming for a fourth successive title at the event, needed 61 minutes to overcome his 51st-ranked opponent 6-3, 6-3 in a second-round match.
Seppi held his own for much of the match but was outgunned on the key points.
Fourth seed Marin Cilic, attempting to win his third ATP title of the season, beat Germany's Philipp Petzschner 6-4, 6-4 in a first-round meeting of two big servers.
The Croat blasted 14 aces to set up a second round meeting with Viktor Troicki of Serbia on Thursday.
Brilliant Safin shines in the dark
Prakash advances to quarters of challenger event
Somdev bows out of Seoul Challenger
Devverman inches closer to top-100 spot
Spotted: Wimbledon champion Roger Federer