  The concept of Berry curvature is essential for various transport phenomena.
However, an effect of the Berry curvature on magnetochiral anisotropy, i.e.
nonreciprocal magneto-transport, is still elusive. Here, we report the Berry
curvature originates the large magnetochiral anisotropy. In Weyl-semimetal
WTe2, we observed the strong enhancement of the magnetochiral anisotropy when
the Fermi level is located near the Weyl points. Notably, the maximal figure of
merit $\bar{\gamma}$ reaches $1.2\,{\times}10^{-6} \rm{m^2T^{-1}A^{-1}}$, which
is the largest ever reported in bulk materials. Our semiclassical calculation
shows that the diverging Berry curvature at the Weyl points strongly enhances
the magnetochiral anisotropy.
