The 25-year-old, who is promoting 'The Amazing Spider-Man 2' in Australia, appeared in a radio show yesterday, reported E!Online.
When she was told that Mel B, 38, who often co-hosted the programme, was unable to attend the sit-down, Stone became emotional.
"Wait, Mel B, could have been here? I'm gonna cry," Stone said.
Mel B, who was also known as "Scary Spice", surprised Emma by talking to her Live on the show.
"Oh my god, is Mel B talking to me? Oh my god, I'm so excited. I'm legitimately crying. I'm the biggest Spice Girls fan ever," Stone added.