  The nonminimal coupling of the kinetic term to Einstein's tensor helps the
implementation of inflationary models due to the gravitationally enhanced
friction. We calculate the parametrized post-Newtonian (PPN) parameters for the
scalar--tensor theory of gravity with nonminimally derivative coupling. We find
that under experimental constraint from the orbits of millisecond pulsars in
our galaxy, the theory deviates from Einstein's general relativity in the order
of $10^{-20}$, and the effect of the nonminimal coupling is negligible if we
take the scalar field as dynamical dark energy. With the assumed conditions
that the background scalar field is spatially homogeneous and evolves only on
cosmological timescales and the contribution to stress--energy in the solar
system from the background scalar field is subdominant, the scalar field is
required to be massless.
