Extra-role behaviors play a special role in achieving organizational goals as well as in individual and social well-being. Therefore, they are considered one of the most important and common topics for review and research in organizational studies. Accordingly, the purpose of this study was to present a model of extra-role behaviors of employees. The research method was qualitative and based on grounded theory. In line with the principle of theoretical saturation, 16 employees and managers of the Kerman Governorate were selected through purposive and theoretical sampling, and interviews were conducted. The data were analyzed using Strauss and Corbin’s constant comparative method (2015) with open, axial, and selective coding. In total, 260 open codes were extracted, which after final analysis were categorized into 73 subcategories and 21 main categories. In selecting participants, efforts were made to ensure that employees from all age groups and employment categories were included. Extra-role behaviors were identified as the core category, while individual characteristics, organizational features, job conditions, support, and rewards were identified as causal and contextual conditions across five levels: organizational approach, organizational commitment, individual conditions, personality traits, and individual health. Intervening conditions were categorized into organizational features and management style. The strategies for extra-role behaviors included spirituality, support, establishment of information systems, performance evaluation, training, flexibility, and goal setting, each with different subcategories. The consequences were classified into three groups: general, organizational, and individual. According to the research findings, the proposed model of employees’ extra-role behaviors is a comprehensive model that, if implemented, can take positive steps toward strengthening strategies for extra-role behaviors among employees.