Song earned 137 caps for Cameroon during an international career spanning almost 17 years, competing at four World Cups and eight Africa Cup of Nations finals.
He played club football in England at Liverpool and West Ham United, and also had stints in France, Germany, Italy and Turkey. The 45-year-old has been serving as coach of Cameroon's under-23 team.
Conceicao led Cameroon to third place at the Africa Cup of Nations finals last month but the Portuguese-born coach has been told his contract will not be renewed.
"The upcoming assignments for our national team require a new orientation and a new breath," said Cameroon Football Federation (Fecafoot) President Samuel Eto'o in a statement.
A separate statement from Fecafoot did not give details of Song's term of contract but said, "Rigobert Song and his team don't have time to pop the champagne corks as their first big challenge is in a few weeks".
Cameroon host Algeria in Yaounde on March 25 and then play a return game in Blida on March 29 with the winner of the playoff tie qualifying for the World Cup in Qatar.
