  We present a complete one-loop renormalization of the Special Galileon
$S-$matrix. Especially we give a complete list of the higher derivative
operators which are necessary for one-loop on-shell renormalization and prove
the invariance of the one-loop on-shell effective action with respect to the
Special Galileon symmetry. This enables us to enlarge the validity of the
enhanced $O(p^3)$ soft behavior of the scattering amplitudes to the one-loop
level. As an illustration we discuss explicitly the four-point and five-point
one-loop scattering amplitudes and comment on some conjectures appearing in the
existing literature.
