A photo, which has emerged from the dinner date, shows Rihanna, 27, sitting across the table from the French sports star while talking to friends who joined them for the evening.
An eyewitness told E! News of the meal: "Rihanna and Karim were [seated] across from each other.
"There were about four people at the table and a few more on another table from the same party. They came separately and they were speaking French at some point."
Earlier in the night before they visited the 24-hour diner, the rumoured new couple are said to have partied at The Griffin nightclub in the Meatpacking District.
This is not the first time the stars have been paired together – romance rumours were sparked during the 2014 FIFA World Cup when the Diamonds hitmaker tweeted her commiserations to Benzema, also 27, when France were knocked out of the tournament.
With Benzema now on the scene, it appears that the increasing dating rumours between RiRi and The Wolf Of Wall Street actor DiCaprio have fizzled out.
Speculation that the pair were in a secret relationship had swirled for several months after they were spotted on nights out a number of times, however, the Grammy-winning singer shut down the reports in March.
The pop star told Hello! magazine: "It sounds to me like you should stay away from the blogs because they will screw you every time.
"I'm so busy right now that I just don't have a lot of time to offer to a man so it wouldn't even be fair to be thinking of pulling somebody else into this life.
"But if I did, he would have to be man enough to live with my schedule and not get scared."