The company had previously forecast adjusted profit for 2020 between $760 million and $780 million.
Greater China revenue per available room (RevPAR) has been affected due to the impact on demand outside the country following corporate travel restrictions in North America and Europe, the hotel chain said.
RevPAR is a key metric to measure a hotel's financial health and is calculated by multiplying the average daily room rate by the occupancy rate.
"This is an evolving situation, and our ability to assess the financial impact of COVID-19 on our business continues to be limited," Chief Executive Officer Mark Hoplamazian said.
Larger rival Marriott International Inc last week warned the outbreak could significantly hurt its full-year results and it was unable to estimate the full financial impact.
Hyatt's shares were down 1.5% at $75.91 in extended trading.
(Reporting by Ankit Ajmera and Neha Malara in Bengaluru; Editing by Shounak Dasgupta)