This book is primarily supposed to be used as a textbook on Soil Chemistry and Plant Nutrients. This has been written to fulfil the requirements of the students studying agriculture at the undergraduate level of all agricultural Universities or other educational institutes in India and abroad. However, postgraduate student and research scholars of soil science and allied field may also equally be benefitted. This book is dealing with fourteen chapters covering chemical and elemental composition of Earth and Earth crust; rocks and minerals, their weathering processes leading to soil formation; soil reactions (pH) and its buffering capacity; soil organic matter; inorganic soil colloids such as silicate clays and others; essential plant nutrients, their sources and transformation chemistry in soil; organic manures, chemical fertilizers and biofertilizers, ion exchange reactions and chemical equilibria in soil, soil biology and chemistry of related soil processes; soil erosion and its impact on soil fertility; problem soils such as acid soil, salt-affected soil, submerged or waterlogged soil.