Cristiano Ronaldo, the Portuguese star joined the Saudi Pro League side in January, signing a two-and-a-half year deal worth £173million-per-year.
Ronaldo has netted 12 times in 12 league games since his move to the Middle East and despite receiving a hero's welcome, Rivaldo believes the 38-year-old could be unhappy in his new surroundings.
The former Manchester United and Real Madrid forward has had to adjust to a different way of life but the Brazil legend would like to see Cristiano Ronaldo return to Real Madrid.
"I understand that sometimes the players are fooled by the big contract they sign in Saudi Arabia but then life there is more closed and football is not always as easy as expected," Rivaldo told Mundo Deportivo.
"So, you may be going through a phase of some disappointment and even reflection. If the money you're getting makes up for the not-so-happy life you're living right now.
"It would be good for him and for football to see Cristiano Ronaldo return to Real Madrid to finish his career.
"Of course, the fans have to understand that they cannot demand the same from him as when he was 25 or 26 years old, but he can still help the club in more conquests".
Reports emerged last week that Real Madrid were preparing to offer Ronaldo a return to the club in an ambassadorial role.
Ronaldo's partner Georgina Rodriguez is reported to be unhappy in Saudi Arabia and keen on a return to Spain.
The Portuguese forward has also been linked with a move to Saudi-backed Newcastle United but boss Eddie Howe quickly quashed any talk of a switch.
"A lot of the names aren't accurate. We need to recruit wisely," said Howe.
"We want to discover them before they explode onto the world stage. We need to go underneath, find them young and develop them. I know the direction."