Abstract: 【Purpose/significance】To deeply understand the psychological mechanism of social media users' privacy disclosure decision-making behavior, explore the characteristics and rules of users' privacy disclosure decision-making behavior under the ef‑ fect of psychological factors, and provide and reference for guiding users to prudently disclose private information and promoting the sustainable and healthy development of social media【. Method/process】From the perspective of psychological accounts, combined with privacy computing theory, construct a user black box model. By collecting data through questionnaires to analyze the psychological mechanisms of user behavior, and further combining privacy sensitivity and utility equations to construct an agent based privacy disclo‑ sure decision behavior model, simulation experiments are used to conduct in-depth analysis of the user's psychological decisionmaking process, and to identify the behavioral emergence patterns of user privacy disclosure from individual to group【. Result/conclu‑ sion】The results show that psychological accounts have a positive impact on users' privacy disclosure decision-making behavior, in which the acquisition of accounts has a positive impact on privacy disclosure decision-making behavior, and the loss of accounts has a negative impact on privacy disclosure decision-making behavior. Privacy sensitivity affects users' privacy disclosure behavior by influ‑ encing their disclosure effectiveness; According to the psychological decision-making process and individual behavior characteristics of users, the small-world network is constructed and simulated, and the group characteristics and emergence rules of user decisionmaking behavior are obtained【Innovation/limitation】The research mainly focuses on individual mental accounts and short-term decision-making process. In the future, in-depth research on decision-making differences between different populations can be con‑ sidered, and long-term effects and dynamic changes can be studied by tracking the evolution of individual decision-making behaviors.