West Nusa Tenggara is a province of Indonesia. It comprises the western portion of the Lesser Sunda Islands, with the exception of Bali which is its own province. The province's land area is 19,931.45 km2. The two largest islands by far in the province are the smaller but much more populated Lombok in the west and the much larger in area but much less densely populated Sumbawa island in the east. Mataram, on Lombok, is the capital and largest city of the province. It shares maritime borders with Bali to the west and East Nusa Tenggara to the east.

The Lesser Sunda Islands, also known as Nusa Tenggara Islands, are an archipelago in Maritime Southeast Asia. Most of the Lesser Sunda Islands are located within the Wallacea region, except for the Bali province which is west of the Wallace Line and is within the Sunda Shelf. Together with the Greater Sunda Islands to the west they make up the Sunda Islands. The islands are part of a volcanic arc, the Sunda Arc, formed by subduction along the Sunda Trench in the Java Sea. Slightly over 20 million people live on the islands. Etymologically, Nusa Tenggara means "Southeast Islands" from the words of nusa which means 'island' from Old Javanese language and tenggara means 'southeast'.