The 69-year-old "Godfather II" actor called the rap mogul disrespectful in front of A-list guests including Martin Scorsese and Cameron Diaz, reported New York Post online.
"Bob (De Niro) was sitting at a table, and when Jay-Z went over to say hello, De Niro told Jay that he never called him back. Bob wasn't in any mood to make polite conversation. He told Jay that if somebody calls you six times, you call them back. It doesn't matter who you are, that is just rude," a source said.
The argument was over a song Jay-Z had agreed to record for the Tribeca Film Festival, but the superstar rapper never got back to fellow Tribeca resident De Niro with details about the track.
Jay-Z's wife Beyonce Knowles, with whom he has 10-month-old daughter Blue Ivy Carter, tried to diffuse the situation..
"When Jay-Z tried to make a joke of it, saying he is terrible on the phone, De Niro kept telling him that he was disrespectful.
"Beyonce came over, but that didn't calm Bob down. It was the talk of the party. Everyone was saying there's only one star in New York bigger and badder than Jay-Z, and that's Robert De Niro. He can be quite scary when he's angry," the source added.