Ronaldo hits late Portugal winner on 200th cap against Iceland
The 38-year-old striker steered in from close range in the 89th minute for his 123rd Portugal goal on a night he also extended his men's international caps record in Reykjavik.
Ronaldo received a bouquet of flowers and a certificate to commemorate the landmark occasion, the latest in a long list of records for the former Real Madrid and Manchester United star.
Having scored twice in each of Portugal's qualifiers in March, albeit against Liechtenstein and Luxembourg, Ronaldo failed to find the net in last week's 3-0 win over Bosnia and Herzegovina.
But he again silenced those who have doubted coach Roberto Martinez's wisdom in calling him up, grabbing the winner after Iceland were reduced to 10 men with Willum Thor Willumsson sent off.
Goncalo Inacio knocked the ball across for Ronaldo to turn home in the 89th minute, but the goal was initially ruled out for offside before the decision was overturned and the Portugal captain was mobbed by his team-mates.
Portugal remain two points clear of Slovakia at the top of Group J. Slovakia, who are Portugal's next opponents in September, won 1-0 away to Liechtenstein to stay unbeaten.