  The properties of primordial curvature perturbations on small scales are
still unknown while those on large scales have been well probed by the
observations of the cosmic microwave background anisotropies and the large
scale structure. In this paper, we propose the reconstruction method of
primordial curvature perturbations on small scales through the merger rate of
binary primordial black holes, which could form from large primordial curvature
perturbation on small scales.
