The chief minister had a one-and-a-half hour meeting with Mr Ambani soon after reaching Mumbai, where she is scheduled to attend a business conclave on Wednesday.
Ms Banerjee later told reporters that Mr Ambani would attend the Bengal Global Business Summit organised by her government in January 16-17 in Kolkata.
"They are already investing in the state. I told him to invest more. The good news is that he has agreed to take part in the BGBS," she said.