The invention discloses a ruthenium metal olefin metathesis catalyst formed by a novel olefin ligand and ruthenium Cabbeen and application thereof. Easily-obtained substituted salicylaldehyde with a simple structure is used as a starting material for simple synthesis to obtain a required olefin ligand, and the corresponding novel ruthenium metal catalyst can be obtained by ligand exchange between the olefin ligand and a catalyst precursor. The catalyst can efficiently catalyze olefin metathesis and catalyze ring-closing metathesis of various dienes to obtain ring compounds and ring-opening metathesis polymerization of dicyclopentadiene. The method is easily-obtained in raw materials, simple in operation, stable in process, environmental friendly, and suitable for amplification production, and a very good method and idea is provided for preparing various macrocyclic drug molecules and super-performance polymer materials by use of the olefin metathesis catalyst.