This paper aimed to study the process of changes in Metropolitan Area Network (MAN) in north of Iran during the last 50 years. The current study tried to determine the most appropriate and standardized number of population in urban areas and to find out how population balance may be kept in one area. This study is an analytic-descriptive research. With the help of population of population estimation of northern cities dated to 1400, This research made an attempt to plan the population standard up to 1400 horizon. This research also aimed to design a plan for increase or decrease of the rate of urban population growth to make a spatial balance in northern metropolitan areas. To this end, adjustment rank-size model suited to entropy rate of metropolitan areas is being designed. The results show that the Entropy rate in those urban areas during the treatment is not being in balance and is decreased from 0.782 in 1335 to 0.769 in 1390.The most irregularities in metropolitan areas are observed in cities with more than 100 population. During the last 55 years population recession in cities with over 5000 people is shown as 1.267, negatively. With the current population growth based on rank size model northern metropolitan areas over 50000 people in number have the population fraction.