Kampung originally recognized as "village" in the Indonesian language, currently indicates a densely populated urban residential area where many migrants from rural areas reside. Because of the lack of urban infrastructures, poverty, and low-quality houses, people in Kampung districts are vulnerable against various health risks. The purpose of this study is to capture the current indoor thermal environment and thermal characteristics of building envelopes of low-cost dwellings in a Kampung, and to present affordable countermeasures against future climate change. Under these circumstances, a field measurement and survey were conducted in the Pasar Kliwon district, Surakarta City, by an interdisciplinary team aiming to comprehensively understand the urban and architectural conditions. In this project, the room air temperature and relative humidity of 16 dwellings were measured every 10 minutes within one week of the summer period (from the 1st to the 7th of April 2019). As a result, the observed room air temperatures have demonstrated significant differences ranged from 28.7 to 33.2 o C among dwellings owing to the diverse design, materials, and quality of buildings. The estimated thermal comfort indices based on the observation data suggest a high ratio from 23% to 30% temperature reached more than 30 o C of the total measured hours and it is evaluated as a time of thermal discomfort. Hence, there arises a necessity to improve the thermal shelter function of the envelopes.