In this paper, we report for the first time making multi-gate buckled self-aligned dual Si nanowires including two sub-100 nm cross-section cores on bulk Si substrate using optical lithography, hard mask/spacer technology and local oxidation. 0.8 GPa uniaxial tensile stress was measured on the buckled dual nanowires using micro-Raman spectroscopy. The buckled multi-gate dual Si nanowires show excellent electrical characteristics e.g. 62 mV/dec. and 42% low-field electron mobility enhancement due to uniaxial tensile stress in comparison to the non-strained device, all at VDS=50 mV and 293 K.