The species diversity of thermophilic cyanobacteria from a geothermal area were poorly studied, especially in Indonesia. This study was aimed to explore the diversity of culturable thermophilic cyanobacteria from geysers in Cisolok Hot spring (90-100°C, pH 7.0-8.0), West Java. Twelve cyanobacterial strains were isolated from this study. Based on morphological characters, these isolates belonging to the orderSynechococcales, Oscillatoriales, Nostocales, and Pleurocapsales. The genera Leptolyngbya, Hapalosiphon, Stanieria, were found in the geyser; while Leptolyngbya, Hapalosiphon, filamentous cyanobacteria, and coccoid cyanobacteria, were found in the river near the geyser. Leptolyngbya was the only genus found in almost all sampling points and this genus grew well in the culture media. Six out of twelve cyanobacterial strains were successfully identified based on partial 16S rDNA sequence data. The sequence homology search by BLAST program showed that the closest relative of strains NBP 10 and NBP 27 were Mastigocladus laminosus (Cyanobacteria, Nostocales) (similarity 96-99%); strain NBP 9 was Leptolyngbia (Cyanobacteria, Synechococcales) (similarity 92%); strain NBP 12 was Oscillatoria (Cyanobacteria, Oscillatoriles) (similarity 99%), and strain NBP 30 was Kovacikia muscicola (Cyanobacteria, Unclassified Oscillatoriales) (similarity 95%). One isolate, NBP 32 has bacteria Pseudoxanthomonas mexicana (Proteobacteria, Xanthomonadaceae) as its closest related taxon, this indicated that strain NBP 32 was mixed with bacteria. Interestingly, three strain (NBP 9, NBP 27, NBP 30) have low similarity to their related taxa, this suggested that they were genetically distinct from their closest related taxon. This finding suggested that the undescribed taxa of thermophilic cyanobacteria have been discovered from the geysers of Cisolok Hot spring. Further study is needed to clarify the identity of these strains.