Berdych used a powerful serve and strong play from the baseline to win in 1 hour, 44 minutes under a blazing sun at Ariake Colosseum.
The Czech player raced to a 5-0 lead in the first set, breaking Paire in the second and fourth games. Paire finally held serve to make it 5-1, but Berdych closed out the set in the next game on serve at love.
"I thought it might be a tough match," Berdych said. "I was actually surprised at how the first set went. He made me work harder in the second set."
The second set was on serve until the fifth game, when Berdych broke Paire to go up 3-2. It seemed Berdych would roll to the win, but in the 10th game Paire battled back, ripping a backhand winner to level at 5-5.
Both players then held serve to send it to a tiebreaker, where Berdych prevailed 8-6 after saving a set point when he was 6-5 down.
"I should have finished it when I was serving at 5-4 in the second set," Berdych stated. "But then I lost my serve and was even down set point in the tiebreak."
Paire, ranked 52nd, made some nice passing shots in the second set, but was hampered by a high number of unforced errors in the loss.
Berdych has one title this season, having captured the indoor event at Montpellier, France, in February.
Earlier, seventh-seeded Stanislas Wawrinka of Switzerland worked to oust Japanese wild card Hiroki Moriya 7-5, 4-6, 6-4. The match was even in the final set until the 16th-ranked Wawrinka broke Moriya to move ahead 4-3.
Lukas Lacko of Slovakia scored a 6-0, 6-2 win over Alberto Ramos of Spain earlier Monday.