Heroin, as the traditional king of drugs, poses significant harm to both the physical and mental well-being of drug users. Its strong addictive nature and high relapse rate exacerbate the difficulty of psychological treatment for heroin addicts. This book focuses on core issues such as emotional processing, attention bias, response inhibition function, decision-making processing, reward processing, among heroin addicts. Based on a series of extensive studies, the book elaborates on important discoveries regarding the psychological mechanisms of heroin addiction in nine chapters, serving as a valuable reference for addiction-related researchers and drug rehabilitation workers, as well as a scientific primer for the general public to understand the psychological mechanisms of heroin addiction.