MT is a geophysical survey method. Based on interpretation of MT data on the YF area, this paper systemati- cally summarized three vertical combination types for a conductive structure, i.e., "three lows and two highs"I, "two lows and one high"II and "three lows and one high" III,introduced their planar distribution features and their interpretation of stratigraphy beneath the Indosinian plane,providing a basis for prognosis of middle and upper Paleozoic residual conditions and for geological comprehensive assessment such as choosing oil and gas exploration areas or zones.