The cities extension, request for developing and increasing underground transportation system. One of this ways in big cities is urban tunnels or metro. Tabriz often located on alluvial deposits, so these tunnels repose in these deposits. In this study we investigate engineering geology aspects of Tabriz Metro line 2, approximately 22 km long. Then it is described about natural temperature measuring of ground layers, and effect of this temperature in metro construction and using. Ground natural temperature is depended on atmosphere temperature and mineralogy of soil and groundwater condition. Some of clayey minerals are radioactive and increase ground temperature. Also, groundwater flowing may affect the ground natural temperature. In metro construction for tunnel boring machine (TBM) and exploitation of tunnel, knowing nature temperature is necessary. In this study, ground natural temperature is measured between 15 and 25 m depth. These measuring shown that the ground natural temperature is between 13 and 18 degrees C.