The defender failed to break into first team during his fledgling season at the San Paolo and will now try his luck with the Gialloblu, who have also parted with Francesco Valiani
The centre-back, 23, arrived only last summer from Newell's Old Boys but barely featured for the Partenopei, having made just four Serie A appearances in 2011-12.
With the likes of Paolo Cannavaro and Hugo Campagnaro already commanding starting berths in defence and Miguel Britos also returning to fitness, Fideleff has opted to look elsewhere for regular first-team football.
He will initially join Parma on loan for the upcoming campaign, with the Ducali then having the option of purchasing 50 per cent of the player's economic rights if he impresses.
Meanwhile, Parma have confirmed the departure of Francesco Valiani to Siena for an undisclosed fee.
The attacking midfielder had been at the Tardini since January 2010, but he will now ply his trade in Tuscany after agreeing a three-year deal with Serse Cosmi's new side.