We report molecular interaction‐driven self‐assembly of supramolecularly engineered amphiphilic macromolecules (SEAM) containing a single supramolecular structure‐directing unit (SSDU) consisting of an H‐bonding group connected to a naphthalene diimide chromophore. Two such SEAMs, P1‐50 and P2‐50, having the identical chemical structure and hydrophobic/hydrophilic balance, exhibit distinct self‐assembled structures (polymersome and cylindrical micelle, respectively) due to a difference in the H‐bonding group (hydrazide or amide, respectively) of the single SSDU. When mixed together, P1‐50 and P2‐50 adopted self‐sorted assembly. For either series of polymers, variation in the hydrophobic/hydrophilic balance does not alter the morphology reconfirming that self‐assembly is primarily driven by directional molecular interaction which is capable of overruling the existing norms in packing parameter‐dependent morphology control in an immiscibility‐driven block copolymer assembly.