This book provides a comprehensive introduction of mesoscale meteorology which is one of the important branches of meteorology, studying majorly mesoscale atmospheric systems. It focuses on introduction of the basic knowledge about mesoscale meteorology. It contains the features and equation set of mesoscale atmospheric motions, the topographically forced mesoscale circulations, the gravity waves in free atmosphere, the front and jet stream, the mesoscale convective systems (MCSs), the atmospheric instability, the factors effecting the development of MCSs, mesoscale weather diagnosis and forecasting. This book provides many figures and basic formulas to help reader understanding the basic knowledge. What is mesoscale weather system? How the mesoscale systems influence severe disaster weather? How to forecast the mesoscale severe disaster weather? You will find the answers in it. This book will be of interest to both graduate students majoring in meteorology and the meteorological researchers.