Introduction: Active aging phenomenon emphasizes optimizing opportunities for health, participation, and security to improve the life quality of elderlies. To achieve this purpose the most important policy is to remove the existing obstacles in society so elderlies could have an active life. This study aims to identify the obstacles and boundaries that faced elder people from having an active life by the concept of “The Right to the City”.
Methods: This research is done by quantitative methods along with thematic analysis. The statistical population consisted of all active elders of Karaj city, among which twenty-three people were selected by purposeful sampling method study population. According to the phenomenological approach of the study, a semi-structured interview was applied to collect the participant opinion based on their life experience. Then, the opinions were provided in a written format and were analyzed through the thematic method.
Results: The result of the analysis showed six main content and twenty-two secondary content in regards to obstacles preventing active aging according to the concept of “the right to the city”. The main contents of the study include “lack of access to urban space”, “lack of security in life”, “lack of welfare resources which fit elder requirements”, “social rejection”, “urban governance infirmity” and “lack of social justice”. 
Conclusions: Results of this study showed that these contents are related to components of the concept of “the right to the city” (participation and space allocation) and due to the mentioned obstacles and boundaries, elderlies are not able to have an active life in Karaj. Due to this study, the most important obstacles that prevent elderlies from having active life are the environmental and social factors of Karaj.