Addiction is a chronically relapsing disease characterized by drug intoxication, craving, bingeing, and withdrawal with loss of control. An expanding body of literature has suggested that non-substance addictions, such as internet addiction and pathological gambling, exhibit shared clinical, phenomenological, and biological features with substance-based addictions. With the development of imaging technology in the past three decades, neuroimaging studies have yielded critical insights into the neurobiological implications of substance and non-substance addictions, revealing neurochemical and functional alterations inherent in the brains of individuals afflicted by these diverse forms of addiction. Imaging techniques have increasingly taken the forefront in elucidating the neuronal underpinnings of addiction as they are poised to guide future research toward developing therapeutic interventions for addiction, particularly for non-substance addiction, which constitutes a growing proportion of addiction disorders. However, the current literature lacks an overview of comparing different types of addictions. This review is set to explore the differences and similarities in neural correlates underlying substance and non-substance addiction based on neuroimaging studies. Specifically, the objectives of this review are (1) to summarize structural brain changes in substance and non-substance addiction and (2) to provide a focused review of commonalities and differences in neural correlates of reward processing, cue-reactivity, and inhibitory control in individuals with substance and non-substance addiction.