The arborescent polystyrene (APS) is used as a precursor to form ordered honeycomb-like microstructured template through self-assembly of water molecules at the air-solution interface via breath-figure mechanism. The APS is synthesized by successive cycles of functionalization (bromination) of polystyrene and grafting reactions via ambient temperature ATRP using the graft-from-graft approach. The resulting polymer film self-assembles to a micrometer-sized honeycomb-like arrangement. The morphology is investigated using AFM and SEM. © 2009 American Chemical Society.