The textbook “Introduction to Graph Theory” has been designed primarily to meet the requirements of B.E./B.Tech students of all technical colleges affiliated to U.P. Technical University. The book will also be fruitful to the candidates appearing in UGC, NET, GATE and other competitive examinations. All the principles and fundamental concepts have been explained very clearly leaving no scope of illusion and confusion. The language used in this book is simple and lucid in style. No previous knowledge of Graph Theory is required to follow this book. The book has been made as much self-contained as could be possible.