The 35-year-old former Brazil forward is adamant that Spain's top two clubs will pit it out in the finale of European football's elite competition and also praised Jose Mourinho
The Catalan giants will face Chelsea in the semi-finals of European football's elite competition, while Real Madrid face a tricky tie against Bayern Munich.
However, Ronaldo is confident that the two Spanish rivals will overcome their tough last-four encounters to reach the showpiece event, which is to be held at Bayern's Allianz Arena on May 19.
"Real Madrid and Bayern Munich are both at a high level and it will be a hard-fought semi-final, but I believe Real will go through," he is quoted as saying by ESPN Brazil.
"Spain is suffering an economic crisis but both teams [Madrid and Barcelona] are at a level much higher than the rest. The Champions League final will be between them."
The former forward then moved on to speak positively of Madrid coach Jose Mourinho, who he believes will stay in the Spanish capital beyond the current campaign.
"He has a winning mentality and tremendous ability to forward in on to the players. He has a great Real Madrid team capable of winning everything. I think he will stay at Real. I do not think he will leave, not until he achieves all of his goals," the 35-year-old concluded.
Ronaldo scored 47 goals in 49 appearances during a one-year spell at Barcelona, while netting 104 times in 177 games for Madrid, enjoying five seasons at the Santiago Bernabeu.
Starting last month and continuing for 10 weeks, Goal.com is publishing exclusive extracts from Luca Caioli's new book, Ronaldo: The Obsession for Perfection. The third extract, published on Friday, looks at Ronaldo's trial and subsequent signing for Sporting Lisbon at the age of 12. Don't miss it!