A hexapod PtRuCu nanocrystalline alloy material is successfully fabricated by a facile approach based on Stranski-Krastanov growth and galvanic replacement and used as an efficient catalyst for direct methanol fuel cells (DFMCs). Due to a synergetic effect of metallic elements in the methanol oxidation, the activity and durability of the prepared PtRuCu/C catalyst is significantly enhanced. It has a mass activity of 1.35 A mgPt^-1 and a specific activity of 3.92 mA cm^-2, which are 3.8 and 8.2 times higher than those of Pt/C, respectively. Its mass activity only decreases 27% after 800 CV cycles compared to Pt/C (60% decline), indicating the admirable stability of the PtRuCu catalyst.