The 26-year-old former Italy Under-21 international, who has made only six appearances for the Blucerchiati this term, joins bottom side Siena in their bid to survive in the top flight.
A statement on acsiena.it read: "Nicola Pozzi is a Siena player. The striker, born in Santarcangelo di Romagna on June 30, 1986, arrives on loan from Sampdoria."
Pozzi signed for AC Milan as an 17-year-old before enjoying successful loan spells with Napoli and Pescara. A prolific five-year stint with Empoli followed with Samp paying 5.2million euros for his services in August 2009.