Passo Oscuro (or Passoscuro) is a small town and beach resort situated in the comune of Fiumicino in the Lazio region of Italy, west of Rome, at the Tyrrhenian Sea, 5 km north of Fregene.

The name Passo Oscuro, Italian for dark step, is said to derive from a hunting path.

The area was donated to the hospital Pio Istituto di Santo Spirito in Rome by the Peretti family, owners of the nearby castle Torre in Pietra.

The modern town was populated during the 1920s mainly by fishermen, and development continued after World War II.

The ending scene of Federico Fellini's La Dolce Vita was filmed on the beach of Passo Oscuro.