The three tourists, who have not been named, were from the Iraqi capital, according to Sulaimani Police Department. They had been visiting attractions in Dukan.
The three bodies were discovered by police after authorities were alerted by the Dukan Swimming Team.
An investigation into the incident has been launched.
Dukan is one of the top tourist destinations in the Kurdistan Region, every year drawing visitors from Iraq and abroad to cool off in the summer heat.
This is the second drowning incident involving tourists visiting the Kurdistan Region in less than a month.
A young Kurdish man drowned in mid-June trying to save a woman from Baghdad also who was swept away in the Choman River in the Balakayati area.
