The quake damaged dozens of single-story houses and taller buildings and was felt in a wider area, including in Bali, where no damage or casualties were reported.
The US Geological Survey said the quake struck at a depth of 7 kilometers.
East Lombok district was the hardest hit with eight deaths, including a Malaysian national, said a spokesman for Indonesia's Disaster Mitigation Agency, Sutopo Purwo Nugroho. The number of casualties could increase as data was still being collected from other locations on the island, he said.
The quake also triggered a large landslide from Mount Rinjani. Authorities were still monitoring its impact.
In East Lombok and the provincial capital of Mataram, it lasted about 10 seconds, sending residents to flee their homes onto streets and fields, Nugroho said. He said most of the fatalities and injuries were caused by falling slabs of concrete.
Photos released by the agency showed damaged houses and the entrance to the popular Mount Rinjani National Park, which was immediately closed for fear of landslides.
Like Bali, Lombok is known for pristine beaches and mountains. Hotels and other buildings in both locations are not allowed to exceed the height of coconut trees.
Indonesia is prone to earthquakes due to its location on the Pacific "Ring of Fire," an arc of volcanoes and fault lines in the Pacific Basin. In December 2004, a massive magnitude 9.1 earthquake off Sumatra triggered a tsunami that killed 230,000 people in a dozen countries. (AP)