After decades of bad publicity as bits of the Unesco World Heritage Site crumbled away under neglect, Culture Minister Dario Franceschini told journalists "here in Pompeii we're turning over a new leaf".
The villa is just one of dozens of houses, shops and streets at the complex which have suffered from years of bad weather and wear, and Unesco had warned Italy the site risked being struck off its heritage list.
Franceschini said Italy would meet a deadline to spend €105 million in EU funds for restoration projects at the site by the end of the year, rejecting fears the money will be withdrawn if the targets are not met.
Three projects have been completed over the past year while another 13 have been launched, he said, adding that the number of visitors rose by 200,000 in 2014 as the race got underway to save the historic area.
"We know well that the world looks with great attention at everything that happens at Pompeii," he said.
The ministry released extracts from a recent Unesco report which praised the "profound change in the behaviour" of those in charge of maintaining Pompeii.
Franceschini said Italy was also hoping to secure money from the private sector to fund other projects at the site, following previous initiatives which have seen donors pay to restore Rome's Colosseum and Spanish Steps.
The Villa of Mysteries is renowned for its burnt orange and red wall-paintings depicting an initiation into the secret cult of Dionysus, the God of wine.
It is one of the few homes to have survived the eruption of Vesuvius in 79 AD pretty much intact, and features a series of fine dining and party rooms as well as a wine-press, indicating the Roman owner was wealthy.
A plaster of Paris cast of one of the bodies discovered under the volcanic debris inside the villa is on display.
The restoration project, which began in May 2013, was carried out in sections to allow parts of the villa to stay open, and focused on reversing damage caused during the 1930s when wax was used to cover and preserve the frescoes.
The site was closed entirely for the last three months to allow repairs to its mosaic floor.
The hugely popular site near Naples has come to symbolize decades of mismanagement of many of Italy's cultural treasures, as well as the fallout from austerity cuts in the country during the economic crisis.
Unesco warned in 2013 of structural shortcomings and light damage at the 44-hectare site in the shadow of Mount Vesuvius, where collapsing walls and houses sparked international concern.
The giant eruption devastated Pompeii nearly 2,000 years ago but the ash and rock helped preserve many buildings almost in their original state, as well as the curled-up corpses of victims.
Take a virtual tour of Pompeii: