Abstract: In this paper, the MTS, DDS and other geophysical data in Tianshui region are ana-lyzed and studied synthetically, the property, state of medium and the thermodynamics condition of the crustal layers in Tianshui region are inferred preliminarily, and their cause of formation and mechanism are interpreted roughly. On the basis of the above mentioned works some problems on the deep-seated physical environment of earthquake activity in Tianshui region are discussed.

Key words: Tianshui region, Property of medium, Deep-seated physical environment