The invention discloses a bridged metallocene compound with sulfur or oxygen heterocyclic structure, which is adopted as an olefin polymerization catalyst. The invention also discloses a preparation method and an application of the compound. The bridged metallocene compound has a cis-structural formula (I) and a trans-structural formula (II). M is Ti, Zr or Hf; A is S or O; R1 and R2 are C1-C6 alkyl or aryl, and are same with or different from each other; X1 and X2 are independently ligands forming sigma-bonds with M. The bridged metallocene compound cooperates with a cocatalyst, and is suitable for alpha-olefin homopolymerization and copolymerization, and is especially suitable for long-chain alpha-olefin copolymerization, such as ethylene and octene copolymerization. According to the double-cyclopentadienyl bridged metallocene catalyst provided by the invention, a hetroatom-containing ligand is bonded to transition metal; the structures of upper and lower cyclopentadienyl heterocycles of the metal are not the same. The special symmetric structure can be used in alpha-olefin homopolymerization and copolymerization, and brings a high insertion rate of long-chain alpha-olefin.