Martinez replaced Fernando Santos as Portugal boss on Monday and starts his tenure in March against Liechtenstein and Luxembourg for the qualifiers for EURO 2024.
Ronaldo's international future was thrown into doubt after Portugal exited the Qatar 2022 World Cup at the quarterfinal stage.
He was reduced to the role of a substitute for Portugal's final two games of the tournament after losing his place to Goncalo Ramos.
One of the game's all-time greats turns 38 next month, having recently signed for Saudi Arabia's Al Nassr as a free agent.
Ronaldo's exit from Europe raises questions as to whether he has still got it at the highest level but Martinez is not prepared to close the door on him just yet.
"Decisions have to be made on the pitch. I won't rush into decisions. I want to meet everyone, and from today I want to talk and meet all the players," Martinez said at a press conference.
"Cristiano is part of that list. He's had 19 years in the national team and deserves respect, let's talk. From there, it's up to me to make the best list for the European Championships.
"Tomorrow we will start working to meet all the players, and Cristiano is one of them.
"We will start a football process to try to get to know all the players who will be able to join this team. We will give a chance to all players and respect all who are already in the team.
"I'm delighted to have them by my side. It's a process that we have to face naturally, responsibly, and we're going to make important decisions for the team."
