Azadipyrromethene (ADP) dyes have been applied widely in various fields due to their outstanding optical properties. An amphiphilic Cu(II)-ADP dye Ⅰ was designed and synthesized by the coordination of one ADP ligand containing two hydrophobic dodecyloxy chains and one ADP ligand containing two hydrophilic poly ethylene glycol chains with Cu(II). The dye Ⅰ was characterized by 1H NMR, MS, and elemental analysis. UV-Vis absorption spectroscopic studies indicated that the dye Ⅰ self-assembled into J-type aggregates in ethanol/water with bathochromic shift of 89 nm. Further AFM and TEM studies indicated a two-dimensional nanosheets of the aggregates. SAXS experiments indicated a bilayer structure of the J-aggregates of dye Ⅰ.