The comments by Fred Hu come as Chinese regulators are investigating e-commerce giant Alibaba and its affiliate Ant after abruptly canceling the latter's initial public offering (IPO) in November last year.
Alibaba founder Jack Ma, who also controls Ant, has not been seen in public since Ant's IPO debacle.
"I believe he is safe and sound. He remains as an enduring example of a successful entrepreneurship," Hu said in an interview at the Reuters Next conference on Wednesday, without elaborating.
Hong Kong-based Primavera became an investor in Ant's 2016 $4.5 billion fundraising and raised its investment during the $14 billion round two years later that valued the firm at a $150 billion.
Hu, a former chairman of Greater China at Goldman Sachs, serves as an independent non-executive director on Ant's board.
"I do believe that the company (Ant) is highly successful innovator and has really single-handedly created fintech in China as we know it," he said. "I remain optimistic about the future of this company."
Hu declined to comment on the prospects for reviving the IPO.Chinese regulators have set about reining in Ma's financial and e-commerce empires since he publicly criticized the country's regulatory system in October for stifling innovation.
That set off a chain of events that climaxed in November with the cancellation of Ant's $37 billion IPO, which would have been the world's largest.
The regulator also launched anti-trust probes into Alibaba's allegedly monopolistic practices.
Hu said China's recent anti-trust crackdown was in line with global trends but that innovation in the country will not be stifled.