The country's police force has been hunting for Jürgen Hermann since April, when the shooting rocked the tiny principality where violent crime is unusual, sparking a massive manhunt.
"The national police was informed on Thursday afternoon that a dead body had been found in Germany," police said.
"The clothing and jewelry on the body indicate that it may be that of the suspect Jürgen Hermann."
In a separate statement, police in the German state of Bavaria said the body of a man was spotted by a fisherman on Thursday in Lake Constance, which is shared by Germany, Switzerland and Austria.
Given the poor state of the body, German forensic experts were planning dental and DNA tests to identify it formally, they said.
Hermann, an engineer, financier and technology investor is suspected of slaying Jürgen Frick, the boss of Liechtenstein's Bank Frick, on April 7th.
Calling himself the "Robin Hood of Liechtenstein" on his website, he had spent seven years sparring with Bank Frick and the tax haven's government over what he alleged was wrongdoing that had cost him huge sums.
He had also blasted the "financial mafia" which, he alleged, controlled the country of some 37,000 people sandwiched between Switzerland and Austria.
After the fatal shooting in Bank Frick's underground car park, all content on Hermann's website was replaced with the English words: "Catch me if you can, dead or alive, reward 200,000,000 CHF" — or Swiss francs.
Hermann was widely believed to have committed suicide after the killing, with police finding a hand-written confession and clothing near the Rhine River, which flows north from Liechtenstein into Lake Constance.