The former Arsenal man, who is still owned by Barcelona, featured for Cameroon when Volker Finke's men performed poorly at the 2014 FIFA World Cup.
Song has not featured for the national team since being sent off for a bizarre tackle on Croatia's Mario Mandzukic in Cameroon's second match at the World Cup, as the African side went on to finish bottom of Group A.
After initially being left out of the squad for the upcoming Cup of Nations in Equatorial Guinea, Song was brought back into the fold following a minor injury to Sevilla defensive midfielder Stephane M'Bia.
But Song has taken the decision to withdraw from the squad and all further internationals as he looks to focus on his club career.
He confirmed in a statement on his official Instagram account: "Since the World Cup in the summer and my subsequent exclusion from the Cameroon squad for the African Cup of Nations I have taken the decision to retire from international football.
"It is true that there were some discussions of late to include me in the squad for this tournament but I feel after a lot of careful thought and numerous discussions with my family this is the right decision.
"My love for my country will never change but I want to take time to focus purely on domestic football and start to rebuild my career at West Ham United. I wish Cameroon all the best and the team will always be in my heart."
Cameroon get their Cup of Nations campaign underway against Mali on January 20, before further Group D clashes with Guinea and Ivory Coast.
