Abstract: Employees' proactiveness in transforming their environment is one of the most important things that businesses need to get and keep a competitive edge in a rapidly shifting market. Since leader-member exchange (LMX) is a key part of workplace that helps employees reach their goals, it makes sense for employees with a high level of proactive personality to try to change it. Based on social exchange theory, this study constructs a moderated mediation model to explore the relationship between proactive personality and task performance and organizational citizenship behavior (OCB), as well as the mediating role of LMX and the moderating role of benevolent leadership in this relationship. Two studies are conducted. Study 1 collects a sample of 200 employees from various industries and organizations via an online survey platform, and study 2 collects paired data from 44 supervisors and 206 employees via a multi-source, multi-time field survey. Using structural equation modeling to examine the two surveys' data, the research reaches the following conclusions. (1) Proactive personality has positive effects on task performance and OCB; (2) LMX mediates the effects of proactive personality on task performance and OCB; and (3) Benevolent leadership has a negative moderating effect on the relationships between LMX and task performance and OCB. That is, the more benevolent leadership there is, the weaker the positive relationship between LMX, task performance and OCB is. This paper not only helps us learn more about how proactive personality affect employees' task performance and OCB based on a multifaceted view of member, leader and LMX, but it also gives us new ideas and useful information to learn more about benevolent leadership from every angle and in a dialectical way.

Key words: proactive personality, leader-member exchange (LMX), task performance, organizational citizenship behavior (OCB), benevolent leadership