OBJECTIVE Access to affected people pays an important role in United Nation Organization for Coordination and Humanitarian Affairs (OCHA). The aim of this article is to identify the main obstacles of humanitarian access and the humanitarian organization responses to these obstacles and finally suggest some recommendations and strategies. METHODS In this narrative study the researchers searched in different databases. This study focused on the data from five countries in the following areas: access challenges and constraints to affected population and response strategies selected for operations in the affected countries by humanitarian organizations. RESULTS Three main issues were studied: security threats, bureaucratic restrictions and indirect constraint, which each of them divided to three subcategories. Finally, nine related subcategories emerged from this analysis. CONCLUSION Most of these constraints relate to political issues. Changes in policy structures, negotiations and advocacy can be recommended to solve most of the problems in access issues.