Functional and structural changes of regional system are ongoing spatial changes that form patterns of spatial organization, depending on dominant regional forces and factors. Spatial structure of West Azerbaijan province experienced significant changes during 15 years; thus, the present research aim to investigate the manner of spatial distribution of two variables of population and activity, and correlation of these variables with spatial structure of the province during the years from 1996 to 2011. Quantitative method was employed for this aim and urban rank-size index was used to analyze settlement pattern of West Azerbaijan province; Kernel density and Moran method was used to analyze population data; general and local Moran data were used to analyze activity data; and regression method was used to see the degree of correlation between these variables. The results showed that spatial structure of west Azerbaijan was monocentric in 1996 while the of spatial distribution trend of the population and activity indicated decentralization tending toward clustered spatial pattern during 15-year period of time, due to high correlation between the given variables. In other words, some kinds of decentralized convergence took place. Such trend would change the spatial structure in West Azerbaijan province and needs to be properly oriented in the future planning of urban and regional development.