Wales Women earned their first Six Nations win to boost their hopes of qualification to the 2014 World Cup in France.
The European tournament's top four automatically go to next year's event.
And following opening defeats by and Rhys Edwards' side edged a tight contest at Stadio Pacevecchia in Benevento.
Catrin Edwards (try), Lowri Harris (try) and Laura Prosser (two penalties) scored Wales' points against Italy.
Coach Edwards said: "Fair play to the girls, they followed the game plan brilliantly and Italy didn't have any answers.
"I can't single out any players because each and every player contributed to a fantastic win.
"There's no reason why we should fear anyone after picking up the victory against what has been a very impressive Italian side this season."
Wales' tournament continues at Glasgow's Scotstoun Stadium on Sunday, 10 March and ends against England Women at Aberavon's Talbot Athletic Ground seven days later.
Italy Women: Manuela Furlan (Benetton Treviso); Maria Diletta Veronese (Valsugana Rugby Padova); Maria Grazia Cioffi (Red&Blu Rugby); Paola Zangiroalimi (Valsugana Rugby Padova); Michela Sillari (Rugby Colorno); Veronica Schiavon (Sitam Riviera del Brenta); Sara Barattin (Rugby Casale); Flavia Severin (Benetton Treviso); Silvia Gaudinio (capt, Rugby Monza 1949); Michela Este (Benetton Treviso); Alice Trevisan(Sitam Riviera del Brenta); Cristina Molic (Sitam Riviera del Brenta); Lucia Gai (Sitam Riviera del Brenta); Sara Zanon (Benetton Treviso); Melissa Bettoni (Rugby Sassenage Isere).
Replacements: Debora Ballarini (Mustang Rugby Pesaro); Marta Ferrari (Sitam Riviera del Brenta); Ilaria Arrighetti (Rugby Monza 1949); Giuliana Campanella (Red&Blu Rugby); Cecilia Zublena (Rugby Sassenage Isere; Vanessa Chindamo (Rugby Monza 1949); Michela Tondinelli (Benetton Treviso); Sofia Stefan (Valsugana Rugby Padova).
Wales Women: Dyddgu Hywel (Caernarfon), Rafique Taylor (Sea View), Elen Evans (Waterloo), Rebecca De Filippo (Cardiff Quins), Philippa Tuttiett (Cardiff Quins), Elinor Snowsill (Bristol), Laura Prosser (Pontyclun); Jenny Davies (Waterloo), Lowri Harries (Neath Athletic), Catrin Edwards (Cardiff Quins), Gemma Hallett (Pontyclun), Shona Powell Hughes (Neath Athletic), Catrina Nicholas (Cardiff Quins), Nia Davies (Cardiff Met), Rachel Taylor (Bristol - Capt)
Replacements: Carys Phillips (Cardiff Met), Bethan Howell (Seven Sisters), Megan York (Blaenau Gwent), Vicky Owens (Pontyclun), Delyth Davies (Cardiff Met), Amy Day (Unattached), Leila Johns (Unattached), Caryl James (Cardiff Quins)