Pavic sealed the result in style, with a slashing forehand drive down the inside line.
"We have been getting better and better this week," said Venus. "We stuck to our game plan and everything came off."
They face fourth seeds Eric Butorac (USA) and Scott Lipsky today, after the Americans beat Julian Knowle and Oliver Marach 6-1 6-4 yesterday.
"They have more experience than us," said Pavic of today's opponents, who have won 30 titles between them compared to one for Venus and Pavic. "[But] we have to set a good game plan and hope for the best."
Meanwhile Venus is thriving on his home court, aiming for more history after last year's singles heroics.
"I love this court," said Venus. "I practiced here all November and December so I am really enjoying it."
The doubles final starts at 12.15pm, with the singles between Jack Sock and Roberto Bautista Agut set to go from 2:30pm.