Marcus Aemilius Lepidus (died c. 77 bc, Sardinia) was a Roman senator who attempted unsuccessfully to overthrow the constitution imposed by the dictator Sulla.
Although he had supported Sulla’s rise to power and became wealthy in the Sullan proscriptions, Lepidus was elected consul for 78 with the help of Pompey, despite Sulla’s opposition. When Sulla died in 78, Lepidus sought to rescind the dictator’s measures. He called for the renewed distribution of cheap grain, the recall of exiles, the restoration of confiscated lands, and, ultimately, the reestablishment of the office of tribune. When his proposals were rejected by the Senate, he gathered forces in Etruria and Cisalpine Gaul and marched on Rome, demanding reelection to the consulship for 77. After being repelled by the other consul, Quintus Lutatius Catulus, at Rome’s Milvian Bridge, Lepidus was driven by Pompey into the port of Cosa (modern Ansedónia) in Etruria. From there he escaped to Sardinia, where he died shortly thereafter, having suffered a series of defeats at the hands of the propraetor, Gaius Valerius Triarius. His son Marcus Aemilius Lepidus was one of the triumvirs who ruled Rome after 43.