A prosecutor asked FIFA to explain why it chose light-skinned model Fernanda Lima and her white husband Rodrigo Hilbert instead of soap stars Lazaro Ramos and Camila Pitanga, who had been mooted as possible hosts.
Sao Paulo state prosecutor Christiano Jorge Santos was quoted as saying in The Sun: "Racism is a serious matter in Brazil. We need to find out if a crime was committed. We do not want the image of our people to be whitened or distorted."
But FIFA insists it opted to go with Hilbert and Lima because they were simply the better people for the job.
World football's governing body said that there will be black and mixed race people taking part in the draw, which will be held in the city of Salvador in the north-east of Brazil.
FIFA also pointed out that it has a good track record of appointing black people to present major events. Ruud Gullit has presented the Ballon D'Or show for the past two years, for example.
A FIFA spokesman said: "Racism is a very serious problem. FIFA takes racism seriously, but this is a ridiculous story and trivialises the real problem.
"We are basing this decision on quality and not colour of skin."