In order to get in sights in to the subsurface structure and lithology in Tadipatri area where gas is gushing out along with the ground water from irrigation wells in the year of 2007, in few villages of Putluru and Yellanur mandals of Ananthapur District A.P, South western part of Cuddapah basin. Magnetic investigations are carried out along all available approach roads and tracks in the region with a station interval of 200 m to give a fairly even distribution of magnetic values for the entire region covering the total an area of 10 sq.km. From qualitatively analysis of Magnetic data with analytical techniques, brought out several lineaments faults, fractures and geological contacts. From Total Magnetic Intensity (TMI) structural map inferred subsurface structures, a total eight highs and two lows seven faults were inferred revealing the structural configuration of the region. From 1st Vertical Derivative and tilt maps were brought out deep seated sills and shale bodies in the Gas show area. From Coefficient of Variation Map of magnetic data clearly delineated eight tectonic disturbed zones (A, B, C, D, E, F, G & H) various faults and other lineaments/dykes. They are emplaced in the south western region of the Cuddapah basin during a crust – mantle interaction and acted as a source for the outcropping dykes, sills and flows are responsible by methane gas leakage. The sills are presumably acting as cap rocks for the gas rising from deeper levels.