This study addresses focused ion beam (FIB) patterning guidance effect on the nanopore development during the subsequent anodization on uneven surfaces. Different shape, uneven features are first created on aluminum surfaces. After that, hexagonally arranged nanoconcaves with different inter-concave distances are patterned across the surfaces. The pore development in different anodization electrolytes as well as with different interpore distances and feature surface curvatures are studied. The results show that FIB guided anodization can produce ordered nanopore arrays on various uneven surfaces. In the nanopore depth direction, pores grow perpendicularly to the tangential direction of the surface, which leads to pore splitting or termination based on the surface curvature. (C) 2011 Elsevier Ltd. All rights reserved.