A series of Mn-complexes with tetradentate N 4 ligands, introducing aromatic groups into 2-pyridylmethyl positions of N,N′-dimethyl-N,N′-bis(2-pyridylmethyl)ethane-1,2-diamine ( mep ), N,N′-dimethyl-N,N′-bis(2-pyridylmethyl)cyclohexane- trans -diamine ( mcp ), have been synthesized and applied for epoxidation of olefins using H 2 O 2 as the oxidant. The Mn-complexes still possessed an octahedral mononuclear structure in a cis -α topology. These complexes showed good regioselectivity, high yields and turnover frequency (even up to 228,000 h −1 ) with low catalyst loading (0.1–0.01 mol%) for epoxidation of a family of olefins (including internal aromatic olefins, internal and terminal aliphatic olefins and diolefins).