The purpose of this paper is to explore dimensions of open government in tax affairs organization of Iran country as a governmental organization. Three main factors of policy, culture, and technology were identified after investigating open government's plan in the United States of America, Austria, Mexico countries and the conducted interviews with experts in three fields of information technology, Executive, and legal. Four subfactors of internal directive, legal, strategic planning, and performance for policy and five subfactors of security, tools, open government program, data, and infrastructure for technology and six sub-factors of employees readiness, communicational channels, knowledge management, changes management, agency stakeholders, and participatory activities were considered for culture. A structured interview was conducted with three experts in legal, information technology and administrative fields for initial evaluation and finding new factors. The statistical population in this research was considered among Tax Affairs Organization of Iran country's employees. The mentioned pattern was evaluated based on partial least squares approach and confirmed at strong level after extracting information from the distributed questionnaires. Three factors of policy, technology and culture have effect on open government and between them culture has the main priority.