The 85 year old has been on a fundraising tour for the Muscular Dystrophy Foundation of Australia.
He was set to perform at a sold-out show in Sydney on Friday but reportedly had trouble getting out of the car and was then taken to the hospital.
"Unfortunately, a combination of a very long trip from Las Vegas, as well as a very busy schedule, and of course when Jerry lands he goes at it 110 percent, led to him feeling very exhausted," said Stephen Cesarano, sales manager of the venue Doltone House. "This is only the third show in 80 years that Jerry has cancelled."
Many in the crowd of 750 refused refunds, instead donating the money to the Muscular Dystrophy Association.
It's unclear if Lewis will be able to perform at another big fundraiser scheduled for next week in Melbourne, Australia.