Multinuclear metal thiolate complexes represent an important class of organometallic compound owing to their capacity that they can not only serve as bio‐mimicking functional platform but can also play as excellent cooperative catalysts. In this context, it is of long‐standing interest to construct new‐type transition metal complexes featuring sulfur donors. Herein we describe a synthetic method toward a novel unsymmetric β‐diketiminate ligand containing a thioether tether in a gram‐scale. This sulfur functionalized β‐diketiminate ligand was proved to be an ideal structural skeleton for coordination and stabilization of relatively unstable FeII and CoII ions to generate new thiolate‐bridged bimetallic complexes. These new complexes have been well‐defined by various spectroscopic characterizations and single‐crystal X‐ray diffraction analysis.