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This paper reviews our study aimed at identifying hydrothermal alterations to surface minerals as a result of volcanic activity at the Wayang Windu geothermal field, which is in a southern volcanic complex on the island of Java. The characteristics of hydrothermal alterations in Wayang Windu are related to surface manifestations. The geologic conditions are that it lies within andesitic, volcanic highlands formed by a concentration of volcanic centers in this part of the Sunda Arc. The geothermal manifestations are related to faults that are affected by volcanic activity, and the geothermal area is characterized by zones of intensive surface alteration at fumaroles and hot springs. There were 17 soil samples collected during a field survey and then analyzed in the laboratory using primarily X-ray diffraction (XRD). The results show that the alteration mineral assemblages observed are strongly associated with surface manifestation intensity. The presence of silica, kaolinite, halloysite, and alunite minerals identified the location as part of an advanced argillic alteration zone in the surface area.