Risk decision refers to the process in which an individual makes an optimal choice by comparing the probability and value of the result brought by each choice from two or more options. At present, questionnaire and experiment methods are used to measure subjects' preference for risk decision making. It is found that risk decision is mainly affected by decision object, external environment and decision maker. Event‐related potentials and functional congratulatory resonance imaging are commonly used to study the brain mechanisms associated with risk decision making.