The first leg of the last-16 tie at the Santiago Bernabeu saw French midfielder Adrien Rabiot give a lead to PSG. Ronaldo pulled one back for his side after he converted from the spot-kick before the break.
Zinedine Zidane introduced Marco Asensio in the final quarter of the game. The 22-year-old provided two assists in quick succession that saw Real take the lead twice at home. Ronaldo finished the match with a brace, which saw him score his 100th and 101st goal for Real in the competition.
PSG still have an advantage of an away-goal and a 2-0 win in the return leg in Paris will be sufficient for Unai Emery's side to progress to the quarter-final of the Champions League. The Portuguese international wants Real to push for another win over PSG at Parc des Princes in March in order to make it to the last eight.
"The tie is not over yet. We have to go to Paris to win and to score goals, to be calm and to qualify for the next phase," Marca quoted Ronaldo as saying.
"This was an important victory. We started the match well, but we let in a goal. But this is the Champions League and Madrid have the experience.
"Games last 90 minutes and, at home, we wanted to play a good game. We have a good advantage for the return thanks to those two late goals.
"We knew [PSG] were a very dangerous team with the forwards they have. We knew we had to press them to win the ball. In the second half we waited a little bit, we played better, and we had more opportunities."
Meanwhile, Neymar stressed that it is still too early to say who between Real and PSG will make it through to the next round of the Champions League. He said, "Nothing is decided, the second leg is still to be played."