Abstract: The present disclosure provides a cyclic metal palladium dimer, and a preparation method and use thereof, and belongs to the technical field of photoelectric materials. In the present disclosure, the cyclic metal palladium dimer can be used as a novel phosphorescent light-emitting material for organic light-emitting diodes (OLEDs), thus solving the problem of insufficient existing phosphorescent materials. Moreover, this dimer provides a new idea for the use of Pd metal in the structural design of phosphorescent materials.