The cabinet reshuffle was widely expected as March 31 is the deadline for top public officials to resign in order to run in the Oct. 1 election.
The ministers' departure follow the resignation on Monday of Finance Minister Antonio Palocci, one of the most powerful cabinet members, who quit over persistent corruption allegations.
Among the six ministers who are to step down is Jacques Wagner, Lula's key liaison with Congress and one of his closest aides. Some political analysts said Wagner's departure could further expose Lula to criticism from the opposition during the election campaign.
Wagner is to run for governor of the northeastern state of Bahia and will be replaced by Tarso Genro, former president of the ruling Workers' Party.
The other ministers due to resign are Jose Alencar (defense), Saraiva Felipe (health), Ciro Gomes (national integration), Agnelo Queiroz (sports), and Alfredo Nascimento (transport).
REUTERS SK RN0652