Having scored 46 goals in the Spanish league last season, Real Madrid star Ronaldo is in irresistible form coming into the European championships, to be hosted by Poland and Ukraine.
Germany's defence managed to subdue Ronaldo the last time the teams met when Portugal lost 3-2 in the Euro 2008 quarter-finals and Podolski says the Germans have to do it again.
"He belongs to the best in the world and we have to stop him," Podolski, who is set to make his 98th appearance for Germany, told German daily Bild.
"But we managed that the last time we played against Portugal and we'll do it again on Saturday.
"We have to be aggressive, entangle him in some tough tackles and take away his love of football. But one thing is clear, we have enough players of our own with great potential."
Germany are set to welcome back vice-captain and key midfielder Bastian Schweinsteiger after he shook off the calf strain he suffered in the Champions League final defeat to Chelsea last month.
"He's very important for us," said Podolski.
"He has had some minor injuries in the last few months and now we have to see that he is fit for Saturday and will help us beat Portugal."
Both Portugal and Germany come into Saturday's clash with shaken confidence.
The Germans suffered a shock 5-3 defeat to Switzerland in Basel, then laboured to a 2-0 win over Israel at the end of last month.
Likewise, Portugal were beaten 3-1 at home to Turkey and were held to a goalless draw by Macedonia recently and Podolski said it is important the Germans start the tournament with a strong performance.
"We don't know ourselves how Saturday will go, which is why the first game is so important," said Podolski.
"If we win (he predicted a 2-0 win if they do prevail), it will carry us through the whole tournament, if we lose, we will immediately be under pressure."