The Real Madrid winger scored two and set up one to help his side to a routine victory over Cyprus, which played with 10 men for almost an hour.
Ronaldo started the scoring on a penalty kick in the 38th minute and put in the second goal in the 82nd minute. Danny and Almedia put the game away in the closing minutes.
Portugal began the game on the front foot, dominating possession but unable to make use of it effectively. The first shot of the game came just before the 10-minute mark from new Zaragoza striker Helder Postiga, who shot just wide from outside the area.
Ronaldo went down in the area a couple of minutes later, claiming a penalty, but the referee waved his protests away. One minute later, Helder Postiga found himself through on goal with only the goalkeeper to beat, but he was denied by Antonis Georgallides.
Ronaldo then forced a good save after firing off a low shot from just outside the penalty area. After a quarter of an hour, the Cypriots were still struggling to impose themselves in the match, and Pepe was then denied by a point-blank save after a free kick from Joao Moutinho.
Shortly after the half-hour mark, Georgallides made another good save on the line when Joao Moutinho’s cross was headed towards him.
Two minutes later, there was a moment of controversy for the home side, as midfielder Sinisa Dobrasinovic was sent off after two yellow cards, the second for a handball which gave the visitors a penalty. Ronaldo confidently dispatched the spot-kick to make it 1-0.
Cyprus coach Nikos Nioplias was forced to bring off midfielder Konstantinos Makridis for defender Nikolas Nicolaou, and thereafter until the break chances were few and far between.
The second half began much as the first half had ended, with Portugal on top and dominating the play. Ronaldo was denied by Georgallides with a near-post drive five minutes after the break.
Ten minutes later, Portugal left back Fabio Coentrao hit the post with a low left-footed drive, with Georgallides beaten. That turned out to be the last decent chance for a while as Portugal failed to break down Cyrpus’ stubborn defense, while the hosts were struggling to gain any meaningful possession with 10 men.
With 15 minutes left, Ronaldo fired a low cross shot right across the face of the goal, but Nani and Helder Postiga just failed to get on the end of it.
Two minutes later Ioannis Okkas was put through on goal with a wonderful through ball, however he was harshly judged to be offside, with replays showing he was in line with Coentrao.
With just under 10 mintues to play, Ronaldo played a one-two on the edge of the area with Nani and shot left-footed low past Georgallides. A minute later, the Real Madrid man got past Christou and cut back for Hugo Almeida, with the substitute left to finish off the simplest of chances.
Miguel Veloso almost made it 4-0 with a long-range strike but Georgallides dived well to his left to turn the ball away. Danny, however, did make it four deep into injury time when he latched onto a long ball from Moutinho and slid his effort into the corner.
Paulo Bento’s side go top of Group H after the victory, but ahead of Norway only on goal difference.