To provide a new transition metal complex being a catalyst component capable of producing 1-hexene by trimerizing reaction of ethylene.

There are provided the transition metal complexes represented by general formula (1) (wherein M is a transition metal atom of group 4 in the periodic table; and X¹ to X³ and R¹ to R¹⁹ are each independently hydrogen, halogen, and 1-20C alkyl, 1-20C alkoxy, 6-20C aryl or the like, all of which may have the halogen).