  In this paper, we discuss the non-Guassianity originated from the
$\alpha$-vacuum on the CMB anisotropy. For $\alpha$-vacuum, there exist
correlation between points in the acausal two patches of de Sitter spactime.
Such kind of correlation can lead to large local form non-Guassianity in
$\alpha$-vacuum. For the single field slow-roll inflationary scenario, the
spacetime is in a quasi-de Sitter phase during the inflation. We will show that
the $\alpha$-vacuum in this case will lead to non-Gaussianity with
distinguished feature, of a large local form and a very different shape.
