Thousands spent the night outdoors and tour operators Jet2, TUI and Correndon cancelled flights departing for the island, which is located in southeastern Greece and is popular with holiday-makers for its beaches and historic sites.
One government official told Reuters 19,000 people had been moved away from their homes and hotels, 3000 of them by boat.
Many were assisted by police.
There have been no reports of casualties in the fire.
Greek authorities said the evacuation effort was among the biggest the country had ever conducted.
"We were walking down the road at two o'clock in the morning and the fire was catching up with us", tourist Amy Leyden told Sky News, calling the experience "just terrifying".
"I didn't think we were going to make it," she said, describing being moved from two hotels with her 11-year-old daughter before being taken to the safety of a school in the island's north.
Coast guard vessels and dozens of private boats carried more than 2000 tourists from beaches on Saturday after the wildfire, which has burned for almost a week, was fanned by strong winds and rekindled in the island's southeast.
Many fled hotels when huge flames reached the seaside villages of Kiotari, Gennadi, Pefki, Lindos, Lardos and Kalathos.
Large groups gathered in the streets under a red sky waiting to be taken to safety.
Volunteers fought to extinguish a blaze that blackened the hillside and charred buildings near Lindos, famed for an acropolis perched on a massive rock within medieval walls.
"We have between 4000 and 5000 people now accommodated at different structures," Thanasis Virinis, a vice mayor of Rhodes told Mega television on Sunday.
The evacuees, including residents from the villages, were housed at hotels, indoor stadiums, conference centres and school buildings, fire brigade spokesman Ioannis Artopoios told Skai radio.
"They have been given food, water and medical help," he said.
One British tourist thanked locals for their generosity in an interview with Greek television.
The tourist, who did not give her name, said shops had refused payment for water and food and small boats had taken women and children to safety first, before returning for the men.
The Greek foreign ministry said it was setting up a help desk at Rhodes Airport to work with embassies to facilitate the departure of visitors who lost travel documents.
Footage on social media showed crowds of tourists at the airport.
Tour operator Jet2 said five planes due to take more tourists to the island would instead fly empty and take people home on their scheduled flights.
TUI said it cancelled all outbound flights to Rhodes until Wednesday.
More than 250 firefighters were battling three fronts, assisted by 15 aircraft, state television said.
Civil protection has warned of a very high risk of wildfires on Sunday in almost half of Greece, where temperatures were expected to hit 45 degrees Celsius.
Heatwaves across Southern Europe and many parts of the world could last until August.
Fires are common in Greece but hotter, drier, windy summers have brought more of them in recent years.
Climate change means heatwaves will become more frequent, an advisor to the World Meteorological Organisation (WMO) said on Saturday.
