The double win is the first at Phillip Island since Carlos Checa in 2011, and puts Rea 14 points clear of Honda’s Michael Van Der Mark in the championship standings.
Chaz Davies, runner up in Race 1 and the rider seen as the greatest threat to Rea in the championship, crashed his Ducati 1199 Panigale R at turn 4 on the final lap and finished 10th.
Davies now sits 4th in the championship on 26 points.
After setting the pace in much of the pre-season testing and taking pole position, Tom Sykes was looking for a good result this weekend.
He took the lead in Race 2 and with 12 laps to go ran wide into turn 4, opening a gap for not just his teammate Jonny Rea, but also Michael Van Der Mark (Honda CBR1000RR SP) and Chaz Davies.
A touch by Ducati’s Davide Giugliano while attempting a passing move on Sykes forced both riders wide and allowed Nicky Hayden (Honda CBR1000RR SP) and Yamaha’s Sylvain Guintoli through.
Sykes eventually finished 6th, just over 3 seconds behind Rea. After a 5th place in Race 1 that places him 6th in the championship with 21 points.
The battle for the lead in the closing stages turned into a three way tussle between Michael Van Der Mark, Chaz Davies and Jonny Rea, with each rider taking the lead at some stage.
Rea and Davies made a break from the pack in the final few laps and fought for the win. Davies was particularly strong coming into turn 4 and took the lead briefly, and then made his final unsuccessful attempt on the last lap.
Nicky Hayden had set the fastest lap times towards the end of the race and looked certain to claim his first podium on his first race weekend in WorldSBK, but a desperate move by Davide Giugliano bumped him back down to 4th.
The next round of the championship is at the Chang International Circuit in Thailand from the 11th to 13th March.