The Uruguayan stars in a seven-goal thriller with Lazio as Napoli moves to within three points of league leaders AC Milan.
Edinson Cavani treble keeps Napoli in hunt for Scudetto
Napoli 4 // Lazio 3
Stefano Mauri gave the visitors a half-time lead with a delightful individual goal and the Brazilian Andre Dias put them further ahead 12 minutes after the restart.
Andrea Dossena and Cavani pulled Napoli level only for Lazio to regain the lead with an own goal by Salvatore Aronica.
Cavani equalised again, winning and converting an 82nd-minute penalty after Giuseppe Biava was sent off, and the Uruguayan lobbed the winner in the 88th minute.
Napoli moved on to 62 points from 31 games, staying three behind leaders AC Milan who beat Inter Milan 3-0 on Saturday.
Cavani's hat-trick now puts him level with Antonio Di Natale, the Udinese striker, at the top of goalscoring charts.