Scotland's Naismith facing possible FIFA ban
The incident occurred when Swedish referee Jonas Eriksson was looking the other way but TV footage appeared to show the Everton forward smashing his elbow into Mijailovic's face close to the centre circle.
If found guilty by FIFA the 26-year-old Naismith faces a possible three-match ban and could miss two World Cup ties against Wales and an away qualifier in Belgium.
"We can confirm FIFA has now opened disciplinary proceedings against Steven Naismith," said a spokesman for football's ruling body.
Naismith, who has won 18 international caps, joined Everton at the start of this season after spending five years with Rangers.
The game between Scotland and Serbia ended in a 0-0 draw.