Martinez has been linked in recent weeks with a move to Premier League side Tottenham Hotspur.
However, Luis Manuel Manso says that he expects talks about a new deal to start shortly.
Speaking to O Jogo, Manso said: "We don't want to turn Jackson [Martinez] into an inaccessible player.
"We want to renew his contract but keep more or less the same conditions.
"I don't know for how many more years, we will only know after we all talk."
Porto would reportedly like to increase Jackson Martinez's salary, length of contract and the buyout fee.
It is thought, though, that Manso would prefer to keep the buyout fee the same (an estimated 40 million euros).