The city of Retalhuleu (Spanish pronunciation: [retaluˈleu]) is in south-western Guatemala. It is the departmental seat of Retalhuleu Department as well as the municipal seat of Retalhuleu Municipality.
Retalhuleu stands at about 240 metres above sea level. In 2003 the city had a population of about 40,000 people. Locally it is nicknamed "Reu."