Floyd Mayweather Files Lawsuit Saying He Was Scammed Out of $175 Million

Floyd Mayweather says he got cleaned out to the tune of $175M ... claiming a former close associate ran a years-long scheme that allegedly drained his bank accounts, hijacked real estate deals, pawned off his jewelry and even made his private jet disappear.

According to a bombshell lawsuit, obtained by TMZ Sports, Floyd claims Jona Rechnitz spent years gaining his trust ... before allegedly becoming the boxer's de facto money manager, real estate guy and banking middleman.

Now, Mayweather says it was all one giant setup.

In the suit, Floyd accuses Rechnitz -- along with Ayal Frist, Frist Apex Ventures and attorney Alexander Seligson -- of orchestrating a massive fraud operation that allegedly rerouted millions of dollars through fake investments, unauthorized wire transfers and shady business entities.

Among the jaw-dropping claims ... Floyd says roughly $100M worth of bling was handed over to Miami jewelers for only about $13M in return ... and says a huge chunk of the collection is still sitting with the dealers.

The lawsuit even includes an alleged text exchange where a jeweler threatened to start liquidating Floyd's pieces if payments weren't made ... and Rechnitz allegedly replied, "Agreed thx."

Mayweather also says he wired $7.5M into what he thought was an investment deal ... but claims the investment never happened and the money disappeared. Beyond that, he alleges another $15M tied to a realty settlement was transferred out without his permission.

And it doesn’t stop there ... he says he unknowingly signed paperwork transferring ownership of his Gulfstream jet with the buyer section left blank ... and says he still doesn’t know where the aircraft money went.

Floyd further accuses Frist of falsely presenting himself as a top executive of Vada Properties despite allegedly never holding those positions.