This week Jacques Nacer, secretary general of the club and head of Corsica's chamber of commerce, became the 17th person shot dead in Corsica this year in a troubling spate of high-profile murders.
Nacer had been on the board since replacing Antoine Nivaggioni, who himself was killed in October 2010.
Last month Antoine Sollacaro, a lawyer who was also close to Ajaccio, was shot dead at a petrol station.
Orsoni is a former leader of the Corsican independence movement and survived an attempted murder in 2008. He is under investigation in relation to a killing in 2009.
Speaking to Le Parisien newspaper, Orsoni said he felt "condemned to death by rumours" and declared himself a "priority target".
He said: "Of course I'm scared. I have a family, children, a 78-year-old mother who trembles every day when she reads the papers.
"More than scared, I'm desperate. I don't know how I can get out of this situation. I think I will quit Ajaccio."
France's interior minister Manuel Valls and justice minuister Christian Taubira made an emergency visit to Corsica following Nacer's killing.
Valls said the French government intended to seize control of the situation and would not let the island spiral into a cycle of violence.