Ronaldo was on the verge of missing out on the prestigious tournament as Portugal trailed Switzerland in the qualifying group.
But in the final match against the Swiss, the Real Madrid forward avoided the same disappointment which team-mate Gareth Bale suffered with Wales.
Holland’s Arjen Robben and Chile’s Alexis Sanchez are also among a host of stars who will not feature in Russia.
But Ronaldo will, after his side beat group leaders Switzerland 2-0 to overthrow them and secure top spot.
A Johan Djourou own goal and Andre Silva strike wrapped up the win to book their place in Russia.
And the ex-Manchester United attacker took to twitter this morning, evidently still buzzing from last night’s win.
The 32-year-old post a photo of the squad and management celebrating with arms aloft, captioned with: “Great team effort! Thank you all for your support. Russia, here we come.”
Portugal boss Fernando Santos was also thrilled with the result, claiming he was always confident his side would prevail.
“I always thought it was possible,” Santos said. “I had confidence in my players and luckily they gave me this gift.
“When you have quality and organisation you are always closer to winning. This team came back to play very well, with good ball control.
“Not all of the 90 minutes were perfect but fortunately we won and we are in Russia.”