"This is straight dirty politics 101," Villanueva said in a video he posted Wednesday on Instagram, confirming the suspension.
"Someone complained that my account was somehow harassing the incumbent," he said. "Imagine that - the truth being harassing. Well, we're going to keep harassing with the truth."
The official reason for the account's suspension was unclear.
Spokespeople for his opponent in the campaign, incumbent Supervisor Janice Hahn, said she and her campaign had nothing to do with Villanueva's account suspension.
"The Board of Supervisors has a responsibility to provide for the health, safety and welfare of the county -- all the residents," Villanueva said when he launched his campaign in September. "In that regard, they have failed absolutely, miserably. I cannot find a measure of success in any activity the board has engaged in."
As sheriff, Villanueva clashed repeatedly with the board. He was accused of ignoring oversight and accountability, disregarding subpoenas to appear before the county Civilian Oversight Commission.
Former LA County sheriff Alex Villanueva testifies on deputy gangs
If Villanueva is able to win the election, he would work directly with those supervisors and current L.A. County Sheriff Robert Luna, who beat him in the 2022 election.