In this century, global warming has become the main cause of temperature increase in various regions, including Indonesia. The increase of temperature gives negative effects to livestock such as the reduction of metabolism, reproduction, and performance. One of the most adaptive livestock to heat stress in Indonesia is Bali cattle. The response of Bali cattle to heat stress can be shown by the expression of HSP90 gene. This early study was conducted to understand the profile of HSP90 gene expression in Bali cattle to heat stress in West Sumbawa district, West Nusa Tenggara. Temperature humidity index (THI) was measured to ascertain the heat stress in Bali cattle that bred in West Sumbawa, West Nusa Tenggara and Cipelang district, Bogor as the control for five days in August 2016. The expression of HSP90 gene was observed from RNA isolation of blood samples of two years old Bali cattle, which were taken from venous jugularis. Transcript variants of HSP90 were analyzed by reverse transcription polymerase chain reaction (RT-qPCR). The results showed that THI measurement in West Sumbawa district is higher than in Cipelang district. Furthermore, there is a tendency that the ratio of HSP90 gene expression of Bali cattle in West Sumbawa district is higher than Cipelang district, as a control. Nevertheless, the values of the ratio of HSP90 gene expression in Bali cattle were not significantly different between the districts. However, this research showed that Bali cattle in West Sumbawa district, West Nusa Tenggara may have good adaptability to heat stress.