This book highlights the theories and applications of quantum acoustical imaging which can be considered as a part of quantum technology. It starts with the theories and background principles of this new field in depth.The examples of some present forms of available acoustical imaging which can be considered as quantum acoustical imaging are given such as ultrasonics in the terahertz range with the use of optical transducers for producing terahertz ultrasound and the theory of sound amplification by stimulated emission of radiation (SASER) and principles based on terahertz ultrasound. The SASER transducer is described, followed by the applications of SASER.Other examples of quantum acoustical imaging are the atomic force acoustic microscope (AFAM) and the ultrasonic force microscope. The author’s personal inventions of quantum acoustical imaging are a system based on phonons entanglement based on the quantum property of phonons entanglement and the quantum ultrasound diffraction tomography system.The advantage of quantum acoustical imaging is the defeat of the classical Rayleigh image resolution limit. An unique feature of this book is that it has gone in depth into the quantum theories of acoustical imaging such as phonons entanglement,,superposition principle and the application of transport theory.Quantum microphones and quantum transducers are also introduced with a final chapter on quantum image processing.