IntroductionCoral reefs are important ecosystems that provide goods and services to marine tropical and subtropical regions (Moberg and Folke, 1999). In Peninsular Malaysia, coral reefs are found in several localities off the west coast, south coast, and east coast of the peninsula (Affendi and Rosman, 2012). The east coast of Peninsular Malaysia has extensive development of coral reefs with a total of 323 scleractinian coral species identified (Harborne et al., 2000). The most recent report on the status of hard coral diversity increased this list to 431 species in this region (Affendi and Rosman, 2012). This figure represents approximately 75% of the total number of 571 coral species identified in the South China Sea (Huang et al., 2015).Although coral reefs provide various important ecosystem services to human populations, their health status has been declining due to human intervention together with detrimental impacts of climate change and ocean acidification (Wilkinson, 2008;Jordan et al., 2010;Unsworth et al., 2010). Reef Check Malaysia reported that the coral coverage in several reefs of the east coast region was exposed to high rates of sedimentation resulting from construction and land reclamation activities (Reef Check Malaysia, 2008). These pressures affect reef diversity and distribution by reducing light availability. In addition, tourism activities may also be a major impact causing a decrease in live coral coverage (Jonsson, 2003;Toda et al., 2007). Trampling action by inexperienced snorkelers and scuba divers may have a negative impact that can cause partial mortality of corals (Zakai and Chadwic-Furman 2002;Toda et al., 2007). Besides the natural and anthropogenic factors, the lack of a comprehensive database is impeding conservation efforts towards coral reef ecosystems. Therefore, management action based on comprehensive studies of marine biodiversity should be performed to ensure the conservation and sustainability of coral reef ecosystems.Several studies about coral species diversity were conducted at Tioman Island by Harborne et al. (2000) at seven reef sites, i.e. Batu Malang, Juara Bay, Gut, Tokong Bahara, Seri Buat, Tulai, and Renggis Islands; by Affendi et al. (2007) at several reef sites from Paya to Genting villages; and by Amri et al. (2008) at one reef site in Tekek Bay. The most recent study of generic coral diversity was done by Toda et al. (2007) at three reef sites, i.e. Manggo, Tulai and Renggis Reefs, at this island. It is an important task to keep up-to-date list of corals and perform a continuous evaluation of the status of coral diversity and reef conditions at Tioman Island.This present study describes the generic diversity and distribution of corals at 13 reef sites in the east coast, west coast, and isolated areas of Tioman Island. The classification of coral morphology class score and the coral condition for each reef site were also determined. Data