The book "Fundamentals of Agronomy: Textbook” has been designed to fulfil the requirement of undergraduate students of agriculture faculty considering the syllabus of 5th Dean's committee of ICAR. This book makes an attempt to present the available information on fundamentals of Agronomy in a very simple and lucid language based on the experience of the author. The book contains chapters on Agronomy and its scope, seeds and sowing, tillage and tilth, crop density and geometry, Crop nutrition, manures and fertilizers, nutrient use efficiency, water resources, soil-plant-water relationship, crop water requirement, water use efficiency, irrigation- scheduling criteria and methods, quality of irrigation water, logging. Weeds- importance, classification, crop weed competition, concepts of weed management, principles and methods, herbicides- classification, selectivity and resistance, allelopathy. Growth and development of crops, factors affecting growth and development, plant ideotypes, crop rotation and its principles, adaptation and distribution of crops, crop management technologies in problematic areas, harvesting and threshing of crops.