  We studied the possibility whether the massive primordial black holes (PBHs)
surviving today can be produced in hybrid inflation. Though it is of great
interest since such PBHs can be the candidate for dark matter or seeds of the
supermassive black holes in galaxies, there have not been quantitatively
complete works yet because of the non-perturbative behavior around the critical
point of hybrid inflation. Therefore, combining the stochastic and $\delta N$
formalism, we numerically calculated the curvature perturbations in a
non-perturbative way and found, without any specific assumption of the types of
hybrid inflation, PBHs are rather overproduced when the waterfall phase of
hybrid inflation continues so long that the PBH scale is well enlarged and the
corresponding PBH mass becomes sizable enough.
