Over the past two decades, Non-Governmental Organizations (NGOs) have become pivotal pillars of welfare systems in many countries; however, there remains a lack of a clear theoretical and empirical formulation of the direct and indirect functions of these institutions. The present study was conducted with the aim of providing a comprehensive model of NGO roles within Iran’s social welfare and social security system. Adopting a qualitative approach within an interpretivist paradigm, data were collected through semi-structured interviews with 12 experts, including NGO managers, legal advisors, and faculty members. Data analysis was carried out using the thematic analysis method based on the Attride-Stirling (2001) model, which ultimately led to the extraction of 29 open codes and 5 basic themes. The findings indicate that NGO roles can be categorized into two levels: first, direct service-providing and empowering roles, including health and welfare service delivery, bridging service gaps, and empowering vulnerable groups; and second, indirect advocacy and supervisory roles, such as monitoring health rights, fostering transparency, needs assessment, policy innovation, and inter-organizational networking. The study concludes that NGOs in Iran have been largely reduced to direct, executive roles and, due to significant structural barriers—such as the lack of supportive legislation, financial dependence on the government, and the absence of a unified database—have failed to perform indirect monitoring and policy-making functions. Ultimately, achieving an efficient hybrid welfare system requires a fundamental redefinition of the relationship between the government and NGOs, alongside the establishment of supportive institutional, legal, and financial frameworks.