The Crisis of the Roman Republic refers to an extended period of political instability and social unrest that culminates in the demise of the Roman Republic and the advent of the Roman Empire, from about 134 BCE to 44 BCE.The exact dates of the Crisis are unclear.

Likewise, the causes and attributes of the crises change throughout the decades, including the forms of slavery, brigandage, wars internal and external, land reform, the invention of literally excruciating new punishments, the expansion of Roman citizenship, and even the changing composition of the Roman army.

Modern scholars also disagree about the nature of the crisis.

Traditionally, the expansion of citizenship (with its all rights, privileges, and duties) was looked upon negatively by Sallust, Gibbon, and others of their schools, because it caused internal dissension, disputes with Rome's Italian allies, slave revolts, and riots.

However, today's scholars point out that the whole purpose of the Republic was to be res publica – the essential thing of the people – and thus poor people can not be blamed for trying to redress their legitimate and legal grievances.