Two-dimensional (2D) circular shape nanostructures (e.g., "nano-coins") are ubiquitously present in thylakoids and grana within chloroplasts of plant cells in nature. The design and fabrication of 2D nano-coins with controlled sizes and thicknesses yet remain challenging tasks. Herein, we present a noncrystallization approach to achieve 2D nano-coins from assemblies of a set of zwitterionic giant surfactants. Distinguished from traditional crystallization approaches where the 2D nanostructures with specific crystallographic symmetries are fabricated, the noncrystallization assembly of giant surfactants results in 2D nano-coins that are derived from the separation of assembled 3D multiple lamellar cylindrical colloids with uniform diameters. The diameters and thicknesses of these nano-coins can be readily tailored by varying the molecular length of giant surfactants' tails. The formation of 2D nano-coins or 3D cylindrical colloid suprastructures is controlled by tuning the pH value of added selective solvents. This new strategy opens a door for controlling the shape, size, and size distribution of assembled nanostructures with different hierarchies.