Walesa said in his blog the book amounts to a "barbarian libel" and attempts to revise his life history, Polish Radio reports.
Walesa, who headed the Solidarity uprising that led to the end of Poland's communist government, expressed outrage over a new book that accuses him of being an informer for the communist-era secret police.
"Proper authorities should get down to some serious work to resolve the problem of slander," Walesa told Polska Daily. "It is intolerable that a man so highly merited for his contribution to democracy as I am is regarded with such contempt."
Walesa said he would leave the country as a last resort if he does not get satisfaction through the courts. In the interim, he said he would refuse to participate in any commemorative events and give back his medals and honors.