The present work reports the formation of nanoporous and/or nanotubular structures on lamellar Ti–41at.%Al alloy consisting of α2-Ti3Al and γ-TiAl with different lamellar widths by anodization. Surface morphology of the alloy strongly depends on anodization potential and the phases. Remarkable finding is microstructure-driven selective pore growth—when the lamellar width is larger than the achievable pore diameter at a certain potential, pores can be grown whereas no pores are grown when the width is smaller than the achievable diameter.