PURPOSE: To provide a catalyst for polymerization of olefin composed of a binuclear transition metal compound containing plural metal atoms and ligands composed of a π electron-containing heterocyclic compound and an organometallic compound and capable of producing a polymer exhibiting a wide molecular weight distribution and excellent in shape and processability.

CONSTITUTION: A polyolefin exhibiting a wide molecular weight distribution and excellent in shape and processability is synthesized by polymerizing an olefin in the presence of a catalyst prepared by blending (A) a transition metal compound of formula I [A and B are formula II (E is N, P, As, Sb or Bi; R1 to R4 are each H, silyl, an alkyl, an aryl, etc.), formula III (E' is the same kind as E; R5 to R8 are the same kind as R1); M1 is a transition metal atom belonging to IIIA, IVA, VA, VIA, VIIA and VIII groups in the periodic table; M2 is Ti, Zr or Hf; R9 is H, a halogen, silyl, an alkyl, an aryl, etc.; L is a ligand, an organometallic compound or a transition metal compound; n is 1 to 4; m is 0 to 6] containing ligands composed of a π electron-containing heterocyclic compound and two metal atoms with (B) an organometallic compound.