We propose a chaotic inflation model in supergravity. In the model the
K\"ahler potential has a Nambu-Goldstone-like shift symmetry of the inflaton
chiral multiplet which ensures the flatness of the inflaton potential beyond
the Planck scale. We show that the chaotic inflation naturally takes place by
introducing a small breaking term of the shift symmetry in the superpotential.
This may open a new branch of model building for inflationary universe in the
framework of supergravity.Comment: Some typos are corrected. To appear in Phys. Rev. Let
