Marginalization is a phenomenon in which economic, social, cultural, physical and service-related and in lower rates, safety factors play a role in its emergence and stems from two fundamental groups of rural and urban absorption. The aim of the present study is to examine the trend of marginalization in recent decades and determine the most important factors in the spread of marginalization in Tabriz metropolis. The research methodology of the present study is descriptive-analytic, the kind of the research is applied, and the data collection method is documentary-survey method. In the present study, to determine the validity, expert opinion method was employed. Then, factors and indices influencing marginalization were determined and having applied the obtained parameters, a questionnaire for the evaluation and determination of the most important and the most influential factors of marginalization was prepared. Then the questionnaire was given to the 34 experts, professionals, and highly qualified peoples of the field of renovation and development, urban planning, and urbanism who were indigenous to Tabriz city and were expert in terms of research and expertise related to Tabriz. Finally, the data were analyzed using statistical methods and correlation coefficients in the SPSS software. The findings of the present study shows that in recent years, migration has faced an increase in its amount and that marginalization is under the influence of various factors (economic, social, physical, service-related, cultural) among which economic factors with 29.41 percent is the most important factor in the marginalization trend and social, physical, service-related and skeletal-physical are the other influencing factors in the marginalization trend of Tabriz city with the 23.57, 20.58, 14.70 and 11.76 percent respectively and the unemployment factor which is a sub-part of the economical factor has a significant role in the non-procedural migration to Tabriz city.