This book in English language, which is specially written for all majors of mechanical engineering, is a new comprehensive educational resource for students and graduates of mechanical engineering. This book is written in four sections, including heat and fluid engineering, design engineering, Manufacturing engineering and Automotive engineering. The heat and fluid engineering section consists of eight chapters including heat transfer, thermodynamics, fluid mechanics, compressors, gas turbines and jet engines, refrigeration and air conditioning, steam boilers, power plant engineering and renewable energy. In the design engineering section, the reader gets acquainted with five chapters, including machine design, engineering mechanics, theory of machines, engineering materials and strength of materials. The manufacturing engineering section includes six chapters, machine tools and machining process, Joining, casting, forming, hydraulic and pneumatic and measurement systems. In the automotive engineering section, the reader will get acquainted with five chapters including internal combustion engines, power transmission systems, suspension and steering systems, chassis and body, electrical and electronic systems of the car.