  The existence and uniqueness of the mild solutions for a class of degenerate
functional SPDEs are obtained, where the drift is assumed to be H\"{o}lder-Dini
continuous. Moreover, the non-explosion of the solution is proved under some
reasonable conditions. In addition, the Harnack is derived by the coupling by
change of measure. Finally, the shift Harnack inequality is obtained for the
equations without delay, which is new even in the non-degenerate case.
