The state vote certification process is usually a routine task, and the ultimate resolution in Wayne County propels Biden toward formal victory in Michigan.
Republicans are also trying to stop formal certification of the election results in other swing states, including Arizona, Nevada and Pennsylvania.
Each state certifies its election results and the Electoral College meets Dec. 14 to codify the results.
In Michigan, Trump allies and Republican poll challengers have spent days launching unsuccessful litigation.
In a more rural county, Mohave, election certification was delayed until Nov. 23 in a sign of solidarity with the remaining election challenges in the state.