Vicenzo De Luca, centre-left leader of the Campania region, which includes Naples, said the shutdown would begin at 10pm that night, amid a sharp rise in Covid-19 cases there this month.
"Halloween is this huge piece of nonsense, this huge stupid Americanism that has also been imported into our country," Mr De Luca said in a Friday briefing broadcast on Facebook.
"There we go. Halloween is a moment of idiocy.
"Seeing as we must deal with reality, and seeing as I'm hearing about people already preparing to have parties, from 10pm on the last October weekend, everything will be shut.
Comment: He's actually happy knowing he's making others suffer.
"There will be a curfew. Moving around won't even be allowed."
Halloween has only recently become popular in Italy, but the following day, 1 November, has long been a public holiday in the country to mark All Saints Day.
On Thursday, Mr De Luca also announced he was closing schools in the region for two weeks.
Mr De Luca's comments come just months after he threatened in March to send police with flamethrowers to break up student parties as the pandemic raged.
In September, the 71-year-old was re-elected to his post with 68 per cent of the vote.
Comment: The lockdowns have provided the authorities with the ideal opportunity to unleash their true, tyrannical nature, and hopefully citizens won't forget that they created a crisis and that some used it as an excuse to impose their own will on the public at the expense of their freedom and livelihoods: