The present book “Key Notes on Agriculture Chemistry and Soil Science” has been designed to fulfill this long felt need of students, teachers, researchers and aspirants of competitive examinations. It is designed in such a way that give rapid, easy access to the core materials in a short format which facilitates easily learning and rapid revision. The book carries fundamentals of Agriculture Chemistry and Soil Science. There are 7 chapters elaborating Discoveries, Abbreviations, Terminology, Reasoning: Principles and Concepts, Explanations, Diagrammatic Representation and Short Notes, Formulae and Equations as well as references also included. The most recent information is provided along with a detailed list of references for further reading.