Mlini is located in the municipality Župa Dubrovačka, in Dubrovnik-Neretva County at an elevation of 5 meters above sea level and it covers the area of 0.72 km² (0.28 sq. miles). According to the 2011 census report, there were 968 inhabitants. It is predominantly populated by Croats (91%), but also Serbs (3%) and Bosniaks (3%). Nearby places: Zavrelje, Srebreno, Brašina, Soline, Petrača, Kupari, Plat, Mandaljena, Buići and Čibača.