Purpose: The purpose of this paper is to examine the roles of perceived organizational support (POS) and work status (regular worker/contract worker) in moderating the relationship between participation in decision making (PDM) and perceived insider status (PIS). Design/methodology/approach: Data were collected with survey questionnaires that were administered to a sample of 369 employees from a case company in Taiwan, for which both regular and contract workers constitute the main workforce. After confirming the reliability and validity of the measurements, the authors conducted hierarchical regression analysis to examine the hypothesized relationships. Findings: The mean PIS for regular workers is smaller than that for contract workers in the case company. For the group of contract workers, the positive influence of PDM on PIS is greater for those with lower POS than for those with higher POS. However, the negative moderating effect of POS does not exist for the group of regular workers. Originality/value: This study adds to the existing literature by showing that contract workers, classified as external workers, can experience PIS, and that POS negatively moderates the positive relationship between PDM and PIS for contract workers. The managerial implications are discussed.