Having left Liverpool for Paris Saint-Germain on a free transfer last year, Wijnaldum headed to Roma on a season-long loan deal last week.
Wijnaldum lifted the Champions League and Premier League trophies during a successful five-year spell at Anfield, but his impact was limited during a frustrating 2021-2022 campaign in the French capital.
While the Netherlands international made 38 appearances in all competitions for PSG last season, fellow midfielders Danilo Pereira (2,623), Marco Verratti (2,621) and Idrissa Gueye (2,043) all played more than his total of 1,992 minutes for the Ligue 1 winners.
After becoming the latest arrival of a busy transfer window at the Stadio Olimpico, Wijnaldum said former Giallorossi winger Salah, alongside Kevin Strootman and PSG wing-back Achraf Hakimi, encouraged him to move to Italy.
"First of all, I wanted to come because of the effort the club put in to sign me as a player," Wijnaldum said
"Also, I spoke with Mo Salah and Kevin Strootman about Roma, about the club and the city, and I only heard good stories about it.
"I even spoke with Achraf Hakimi about it, even though he played at Inter Milan, he said [Roma] was a beautiful club and a beautiful place and I would be happy here. So that convinced me a lot.
"I know the club, we played them twice when I was at Liverpool [in the Champions League in 2018], and the atmosphere at the Olimpico was amazing – so I knew that I would be playing for a club with a great atmosphere and beautiful supporters.
"But that was basically the only thing I knew, so I asked for some advice from Mo and Strootman and they had good stories."
Wijnaldum has joined the likes of Nemanja Matic and Paulo Dybala in signing for Roma ahead of the new Serie A campaign, and added the influence of Mourinho was another factor in his decision to head to Italy.
"When I arrived, we spoke more about football things. I think his record as a manager speaks for itself," the midfielder said of the former Chelsea and Real Madrid boss.
"The things he did in football, the prizes he won and the clubs he managed, it's unbelievable.
"I think every player wants to work with him and I am the same. From the moment I spoke to him, I told myself I really wanted to join the club – but that was the case even before.
"I think the thing that convinced me the most was the amount of effort the club, through Mr [director of football, Tiago] Pinto and the manager, put in to sign me. At that moment I felt really wanted and appreciated by the club and that helped me make the decision."