UN war crimes judges at the International Criminal Tribunal for the former Yugoslavia (ICTY) are to hand down their long-awaited judgement on "The Butcher of Bosnia" in The Hague.
Despite the multiple charges against him, which include genocide, Mladic remains a hero to many in Serbia.
"Whatever the verdict... Ratko Mladic remains a legend of the Serbian people," said Dodik, president of Republika Srpska.
"He's the man who put his professional and human capacities at the service of the defence of the Serbian people and their freedom," he was quoted as saying by regional television station N1.
Mladic, 74, denies the charges against him, which include 11 counts of genocide, war crimes and crimes against humanity allegedly committed during the 1992-1995 war that killed 100,000 and displaced 2.2 million as ethnic rivalries tore Yugoslavia apart.
But Dodik said the former military commander had led "an army that defended the freedom of this people and led to the establishment of Republika Srpska".
He said ICTY was going to "deliver a political verdict", one "unfair to General Mladic and to the Serbian people", but that it would be accepted "with dignity".
"I think the myth of General Mladic will only be reinforced by the negative judgement of The Hague tribunal," Dodik said.