  In this paper we report the results of a detailed investigation of the
complete time evolution of massless fermion fields propagating in spacetimes of
higher dimensional stringy black hole solutions, obtained from intersecting
branes in string/$M$ theory. We write the Dirac equation in $D$-dimensional
spacetime in a form suitable to perform a numerical integration of it, and
using a Prony fitting of the time domain data, we determine the quasinormal
frequencies that characterize the test field evolution at intermediary times.
We also present the results obtained for the quasinormal frequencies using a
sixth order WKB approximation, that are in perfect agreement with the numerical
results. The power law exponents that describe the field relaxation at very
late times are also determined, and we show that they depends upon the
dimensionality of space-time, and are identical to that associated with the
relaxation of boson fields for odd dimensions. The dependance of the
frequencies and damping factor of the spinor field with the charges of the
stringy black hole are studied.
