Abstract: Synthesize bis(salicylaldmine)nickel typed complexes with o-toluidine and 2,6-dimethylaniline as a catalyst for propylene dimerization. The complexs were characterristed by IR and UV. And the complexes were tested by DSC thermal properties. Study the Complex / triphenylmethane solution system by UV atlas, suggesting a possible catalytic mechanism of the formation of the active site.