Longwall top coal caving (LTCC) mining method has been used to extract thick coal seams in China. Unfortunately the method has also brought with it an increased risk of spontaneous combustion (sponcom) in active LTCC goafs. It is therefore critical to identify the sponcom prone zones in LTCC goafs so that remedy measures can be taken to prevent sponcom from occurring. One of the successful methods to identify the sponcom prone zones is through the combination of field measurements of temperatures and oxygen concentrations inside a LTCC goaf and numerical modeling. A new technique has been developed specifically to enable the field measurements inside LTCC goafs to be easily undertaken. Presented in this paper are the description of such technique and its successful application in Xinglongzhuang coal mine of Yankuang Group, China.