The article studies relatedness as a property of economic space of a region. Intra-regional relatedness is proposed to be assessed by using the authors’ gravity model that allows to provide “interference” of physical and economic space, and identify “mass centers” of economic interrelations, their strength and vector. The implementation of the gravity model allowed to find out the level of relatedness between cities of Tyumen region. Another stage of the research dealt with the modeling of the impact of economic space relatedness forces on regional development which led to the formulation of variant scenarios of regional development and the estimation of expected per-capita GRP elasticity to relatedness forces changes. The research resulted in the proposal of an administration model for the regional development goal-setting concerning economic space relatedness.