Mljet (Latin Melila, Italian Meleda) is the most southerly and easterly of the larger Adriatic islands of the Dalmatia region of Croatia. Population 1,111 (2001).

Mljet lies south of the Pelješac promontory, from which it is divided by the Mljet Channel. Its length is 23 miles; its average breadth 2 miles. It is of volcanic origin, with numerous chasms and gorges, of which the longest, the Babino Polje, connects the north and south of the island. Port Polače (It. Palazzo), the principal harbour, on the north, is a port of call for tourist ferries.

The northwestern part of the island includes an inland sea as well as a small island within it. It has been a national park since November 12, 1960.

Mljet has been regarded as the "Melita" on which Saint Paul was shipwrecked, this view being first expounded, in the 10th century, by Constantine Porphyrogenitus. As at Malta, a St. Paul's Bay is still shown.