In developing countries, after decades passed from preparing urban development plans, informal settlements and urban decay are unresolved, but their scope and severity increase day by day. Therefore, ins tead of tracing the root of this problem in preparing and implementing plans, it should be viewed from another perspective and the hidden aspect of planning theory, i.e., the realm of power and its application to living space, mainly ignored by urban planners. The primary purpose of this s tudy is to inves tigate the genealogy of urban development plans in the Abkooh neighborhood to reflect the application of bio-power in the process of spatial planning. Using the social cons tructivism approach and accepting the transition of the capitalis t sys tem from imperialism to the empire, the current s tudy analyses two categories of power-knowledge: disciplinary power and bio-power and their relationship with spatial planning. Then, after describing the gray spaces, applying disciplinary power and bio-power in these spaces is discussed. Finally, Foucault's genealogical approach is performed to critically analyze the bio-power in urban development projects related to the Abkooh neighborhood. From Foucault's power-knowledge perspective, power relations seek to accumulate capital and commodify urban spaces through urban development plans and rely on disciplinary power and bio-power and using the formal spatial planning sys tem. The research findings prove that his torically, the formation of urban development plans is connected to the network of power relations. Therefore, spatial planners, besides attending planning approaches routinely learned in the academic environment, should also address power-knowledge issues.
