Cristiano Ronaldo scored twice in the second half to take his tally to 18 Champions League goals in 2017 – the most in a calendar year.
Ronaldo, who broke another Champions League record, helped Real to seal a place in the Champions League last 16.
Zidane’s side have been inconsistent in LaLiga this season but were dominant as they picked up their biggest away win in the competition.
Tottenham beat Dortmund to claim top spot on 13 points, with a game to spare.
Luka Modric opened the scoring for Real with a volley from 25 yard before Benzema, who had only scored twice all season doubled that tally with two neat finishes inside the area, while defender Nacho also headed in.
Ronaldo headed home Marcelo’s cross and then scored from the edge of the area to become the third player in the Champions League era to score in each of the first five games of a season.
He has 18 in his last 10 appearances in the competition – and now 113 in total, 16 ahead of Barcelona forward Lionel Messi.
APOEL will slug it out with Dortmund for third place and a Europa League spot, with both teams on two points.