Divalent samarium bis(phosphido) complex Sm(PPh2)(2) was first applied as an initiator for the ring-opening polymerization of epsilon-caprolactone (epsilon-CL). In comparison to samarium diiodide (SmI2), this Sm(II) complex exhibited much higher activity and yielded poly(epsilon-CL) with higher molecular weight. At the same time, an in-situ generated tetrafunctional samarium enolate from the reduction of 1,1,1,1-tetra(2-bromoisobutyryloxymethyl)methane with Sm(PPh2)(2) or SmI2 has proven to initiate the polymerization of epsilon-CL under mild conditions. The resulting linear and star-shaped poly(epsilon-CL)s have been characterized by H-1 NMR, GPC, and SLS.