The board is planning to vote on whether to remove Villanueva as head of the county's emergency operations center.
On Monday, Villanueva came out and blasted the planned vote.
"If you're asking the public to stay home, cooperate with authorities, the same applies to the Board of Supervisors," the sheriff said. "They need to remain focused on this united front against the spread of the coronavirus so that together we can save lives."
The move is based on a report on the communications efforts after the 2018 Woolsey Fire and comes as more cases of the novel coronavirus in the county are reported each day.
Los Angeles Supervisor Kathryn Barger previously said the motion for the proposed change first came up in November.
Under the role of lead coordinator, the sheriff has been charged with planning for, responding to and recovering from large-scale emergencies.
Supervisors will vote on different items Tuesday, including an update on a county ordinance that would remove the sheriff from the role. If he is voted out, Villanueva would still maintain command over operations and overall law enforcement.
His removal would put Sachi Hamai, county chief executive officer, in charge. Four of five members of the board would need to approve the removal.
Villanueva has slammed the board, accusing them of advancing their own political interests.
Meantime, the sheriff has once again reversed his decision on closing gun stores.
The decision comes after the federal government listed them as essential.
The sheriff says the county will no longer order gun shops to close.