J. Basic. Appl. Sci. Res., 3(8)76-83, 2013 © 2013, TextRoad Publication ISSN 2090-4304 Journal of Basic and Applied Scientific Research www.textroad.com * Corresponding Author: Hamed Rahmani, Department of Management, Qazvin Branch, Islamic Azad University, Qazvin, Iran Study on Mediating Role of Trust in the Relationship between Organizational Citizenship Behavior and Organizational Justice in Service Organizations (Case Study of Welfare Organization of Alborz Province) Hamed Rahmani 1 , Esmaeil Asadi 2 , Fatemeh Sanaee Alam 3 1 Faculty member of Qazvin Islamic Azad University 2,3 PHD Candidate in Public Management, Science and Research Branch, Islamic Azad University, Tehran, Iran ABSTRACT In today organizations, preparing for future changes exerts intense pressures on employees to take responsibility for their job enhancement planning, education and compensation. Also organizations such as welfare ones are willing and trying to select employees who exceed their tasks and job description so that their organizations can meet their needs, satisfy clients and adapt with changing nature of the society. Present paper aims to study mediating variable of trust with regard to the relationship between organizational justice and organizational citizenship behavior. Present research is a descriptive-applied one. Data were collected from interviews and questionnaires. Statistical population consisted of all employees of welfare organization of Alborz province and judgment sampling method was employed. To verify reliability, internal consistency was tested with Cronbach alpha. To verify the hypotheses, structural equation model was used. In total, using Lisrel software two measurement and structural models were exploited for factor analysis, path analysis and model fitness. Research findings showed that there was a significant relationship between all research variables (organizational justice dimensions, organizational justice, trust and organizational citizenship behavior). Finally it was seen that in welfare organization of Alborz Province there was a very significant relationship between employees' trust and their perception of organizational justice (98) and this suggests importance of this variable as a mediator in welfare organization. KEYWORDS: organizational justice, organizational citizenship behavior, trust, service organizations. 1. INTRODUCTION Welfare organization as a service entity was established with a high level purpose. This organization aimed to take appropriate measures and provide services and non-insurance supports while maintaining values and human dignity and relying on public participation and close relationship with relevant organizations in order to promote rehabilitation and support services, prevent disabilities and social harms and help to meet minimal basic needs of low income groups. In today organizations, preparing for future changes exerts intense pressures on employees to take responsibility for their job enhancement planning, education and compensation. Also organizations such as welfare ones are willing and trying to select employees who exceed their tasks and job description so that their organizations can meet their needs, satisfy clients and adapt with changing nature of the society. Employees' behavior in work setting has attracted attention of many researchers over past decades. Various behaviors were studied and analyzed conceptually. These behaviors included pro-social behaviors, extra-role behavior and organizational citizenship behavior. A set of voluntary behaviors employees show in organization , that is out of special requirement range of individual role and directly and explicitly will be recognize by organizational formal reward system (Gilannia, et al, 2012). Present research aimed to study that type of individual behavior in which the individual believes in long-term participation in organizational service success. These behaviors have been neglected in previous research on performance evaluation of employees (Castro, et.al, 2004). A great number of researchers focused on the effects of attitudinal variables on employees' behavior. Researchers state that attitude plays a predicting role in relation to variable of employee behavior. Also some of them presented models for employees' attitude and social norms to explain predicting variables for employees' behavior. According to social exchange theory these types of behaviors mostly represent an internal role. This suggests that attitudinal variables such as trust and organizational commitment are always of a high predictive ability in relation to employee performance but in total they are not able to explain organizational citizenship behavior (Guanling Wang, 2011). Social exchange has usually been conceptualized as a type of relationship based on organizational citizenship behavior (Organ, 1988). From social exchange view, employees' behavior is influenced by exchange relationships. According to Deluga, organizational citizenship behavior can be classified 76