  The total cross section of the process $e^+e^- \to \Lambda\bar{\Lambda}$ is
calculated within the energy range close to the mass of $\psi(3770)$ charmonium
state. Two different contributions were considered: the $D$-meson loop and the
three gluon charmonium annihilation one. Both of them contribute noticeably and
in sum fairly reproduce the data. Large relative phase for these contributions
are generated with respect to the pure electromagnetic mechanism. As a by
product the fit for the electromagnetic form factor of $\Lambda$-hyperon is
obtained for the large momentum transferred region.
