An electron-withdrawing group-containing metal compound (I) of an atom of the
Group III to the Group XII or lanthanide series of the Periodic Table of the Elements,
a catalyst component for addition polymerization composed of the compound (I),
a catalyst for addition polymerization obtained by contacting the compound (I)
with a specific compound (II) of metal of the Group III to the Group XIII or lanthanide
series and optionally an organoaluminum compound (III), and a process for producing
an addition polymer using the catalyst.
