Prosecutor Ettore Torri will now recommend to an anti-doping tribunal, due to meet in the coming days, that the Italy captain should not receive any sanction.
The tribunal will make the final decision.
"The prosecutor asks for the Cannavaro case to be dropped," a statement from the prosecutor's office said.
"We can exclude (the possibility) that Cannavaro is responsible. This office reserves the right to make further judgements in the future over other parties... which were responsible."
It was not clear from the statement who those other parties might be.
Cannavaro received emergency cortisone treatment after being stung by the wasp at Juventus training on Aug. 28 and then failed a dope test after a Serie A match two days later.
The 36-year-old had requested an exemption after being treated for the sting but did not receive the documentation before he was tested.
"I am happy the prosecutor has asked for my case to be dropped because this shows he appreciates my good faith and my behaviour," Cannavaro told www.juventus.com.
"I had no doubt that this would happen and I am sorry that such an insignificant incident generated so much clamour."
He is suspended for Italy's World Cup qualifier in Ireland on Saturday, when a point will put the world champions through to next year's finals, but is due to meet up with the squad on Sunday ahead of Wednesday's home game with Cyprus.
Torri has a reputation for being uncompromising in the battle against doping.
The prosecutor has in the past charged sports personalities even when they have argued their positive tests were the result of accidents.
