A novel binuclear manganese Mn(II) macrocyclic complex with two pyridylmethyl pendant arms, [Mn 2 II (H 2 L)(μ-OAc) 2 ](ClO 4 ) 2 ·H 2 O, has been synthesized and characterized crystallographically and magnetically. The crystal structure of the complex shows that two manganese ions locate in the same head of the macrocycle, leaving an uncoordinating cavity to catch protons through oxide of phenolate and the nearby imine groups in another head. The electrochemical study demonstrates that the complex gives two couples of redox peaks with E 1/2 of 0.3775V and 0.8409V, respectively. The variable temperature magnetic susceptibility measurement on the sample displays weak antiferromagnetic interaction between two manganese (II) with the J=−3.733(7)cm −1 . This complex exhibits a moderate activity for catalyzing disproportionation of H 2 O 2 to O 2 .