Ordos Basin contains concealed sandstone type uranium deposits in the lower Jurassic Zhiluo Formation. The study of the deep-penetrating geochemical methods will contribute to uranium exploration in the basin. The study shows that the collection and analysis of the clay-rich micro-surface soil provides a special application to regional geochemical exploration of sandstone type uranium deposit in the semi-arid terrains. The study of the distribution patterns of R=lnCe+lnY+lnZr+lnNb shows that the mobile forms of uranium should be the key factor causing the variation of the total content in surface soil samples. The application of the extractant of MML-U to selectively leaching the mobile forms of elements from soil along traverses over the Sunjialiang section of Dongsheng uranium deposit well delineated the U, Mo and V anomalies over the concealed orebodies.