The Serbian mafia, or Serbian organized crime, are various criminal organizations based in Serbia or composed of ethnic Serbs in the former Yugoslavia and Serbian diaspora. The organizations are primarily involved in smuggling, arms trafficking, drug trafficking, human trafficking, assassinations, heists, assault, protection rackets, murder, money laundering and illegal gambling. Ethnic Serb organized crime groups are organized horizontally; higher-ranked members are not necessarily coordinated by any leader. The Serbian mafia is estimated to earn €125 billion annually, with its annual earnings on the cocaine market in Europe worth €5.4 billion. According to criminologists and law enforcement authorities, the Serbian mafia is the most powerful in Europe.

Zoran Đinđić, the sixth Prime Minister of the Republic of Serbia, was assassinated on Wednesday 12 March 2003, in Belgrade, Serbia. Đinđić was fatally shot by a sniper while exiting his vehicle outside of the back entrance of the Serbian government headquarters. A state of emergency was immediately declared in the country, and during the police "Operation Sabre", more than 11,000 people associated with organized criminal groups were detained.