Abstract Unexpectedly, a structurally MMO active site‐like new ruthenium complex was synthesized, and it was found that the complex showed high catalytic activity and selectivity for C═C double bond oxidative cleavage reaction, which has been described in this paper. The ruthenium‐catalyzed oxidation reaction of olefins to aldehydes in the presence of NaIO 4 proceeded smoothly under mild conditions to provide aldehyde products in satisfactory to excellent yields without the formation of acid byproducts at all. Due to the formation of oxygen‐bridged bonds in the reaction process, the ruthenium catalyst is very stable, reaching a turnover number of 44,266 and a turnover frequency of 4918 h −1 .