The talks come against a backdrop of unresolved contract negotiations with Ousmane Dembélé.
The French winger is in discussions over an extension but has not yet reached an agreement on his salary, and PSG are reportedly exploring contingency options in the event that situation does not resolve cleanly.
Martinelli fits the profile Luis Enrique seeks in his wide attackers — dynamic, intense in the press, mobile in transition. The 24-year-old has scored 11 goals and provided six assists across 46 appearances this season but has been in and out of the starting line-up at Arsenal, with Leandro Trossard often preferred on the left. His contract runs until June 2027 with an option for a further year.
Campos also held talks with representatives of RB Leipzig winger Yan Diomandé, 19, a younger and more embryonic target whose profile fits PSG's wider recruitment philosophy around high-potential, affordable talent.
Whether Martinelli actually leaves Arsenal this summer is far from certain. He is an important squad member and Mikel Arteta has shown no intention of selling. Any deal would require a substantial offer.
PSG are not short of attacking options — Bradley Barcola, Désiré Doué and Kvaratskhelia all operate in wide areas — but with Dembélé's future uncertain, the club is thinking ahead.
Arsenal face Manchester City on Sunday in a match that could decide the Premier League title.