The paper proposes a new type of modular collapsible reinforced concrete foundation for steel support for various types of structures: power lines, wind power plants, billboards, traffic lights, etc.The foundation has the shape of a cross-hammer in the plan and consists of separate modules manufactured at the factory and connected to each other by concrete dowels and tie bolts on the construction site. At the same time, this technological approach makes it possible to obtain more stable (uniform) strength and deformation properties of both the individual module and the assembled foundation as a whole. Reducing the material consumption is achieved by creating a cavity in each typical module and filling it with local inert material (soil). The central module has an anchor device for joining with the support according to the type of flange connection. This device, along with the use of conventional anchor bolts, involves filling the central module with non-shrinkable fast-hardening steel-fiber concrete. Thus, the positive result of the proposed solution is to increase the bearing capacity of the foundation as a whole, increase the strength and stiffness of its main joints, and simplify installation in comparison with traditional approaches to construction. A comparative calculation of the foundations of the proposed and standard known solutions showed the effectiveness of the first one by at least 17.2%.