  We study the non-Gaussianity in the simplest infrared (IR) model of the DBI
inflation. We show that the non-Gaussianity in such a model is compatible with
the current observational bound, and is within the sensitivity of future
experiments. We also discuss the scale dependence of the non-Gaussianity. In
the DBI inflation, such a feature can be used as a probe to the properties of
the background geometry of the extra dimensions or internal space.
