  We present early spectroscopy of the recurrent nova U~Sco during the outburst
in 2010. We successfully obtained time-series spectra at $t_{\rm
d}=$0.37--0.44~d, where $t_{\rm d}$ denotes the time from the discovery of the
present outburst. This is the first time-resolved spectroscopy on the first
night of U Sco outbursts. At $t_{\rm d}\sim 0.4$~d the H$\alpha$ line consists
of a blue-shifted ($-5000$ km s$^{-1}$) narrow absorption component and a wide
emission component having triple peaks, a blue ($\sim -3000$ km s$^{-1}$), a
central ($\sim 0$ km s$^{-1}$) and a red ($\sim +3000$ km s$^{-1}$) ones. The
blue and red peaks developed more rapidly than the central one during the first
night. This rapid variation would be caused by the growth of aspherical wind
produced during the earliest stage of the outburst. At $t_{\rm d}=1.4$~d the
H$\alpha$ line has a nearly flat-topped profile with weak blue and red peaks at
$\sim \pm 3000$ km s$^{-1}$. This profile can be attributed to a nearly
spherical shell, while the asphericity growing on the first night still
remains. The wind asphericity is less significant after $t_{\rm d}=9$ d.
