It said the memory chips from the Su-24 bomber downed on the Syrian border were destroyed or badly damaged.
The Russians had hoped to prove the plane never entered Turkish airspace, as claimed by Ankara. Work will continue to try to retrieve the data.
The incident sparked a major bilateral crisis, with Russia imposing sanctions.
The Russian military representatives presented their preliminary findings in Moscow on Monday, after opening the "black box" on Friday in the presence of international experts.
Some 13 of the 16 chips had been destroyed, while x-ray tests on the others showed extracting information would be impossible using normal methods.
What we know about how the Su-24 was downed
How Russia's sanctions could hit Turkey
The war of words as it erupted
However, the BBC's Sarah Rainsford in Moscow says further work will be done to see if other methods of retrieving the data are possible.
The Su-24 was shot down by F-16 fighters on 24 November.
Turkey insists that the jet, from the Russian air contingent deployed in Syria in support of President Bashar al-Assad, ignored warnings to leave its airspace.
Both crew members ejected but the pilot was killed, apparently by militants on the ground while the navigator was rescued.
A Russian marine sent to rescue the crew was also killed and a helicopter destroyed on the ground.
Russia says the plane was shot down within Syrian airspace. President Vladimir Putin has described Turkey's action as a "stab in the back" committed by "accomplices of terrorists".
Russia has demanded an apology from Turkey and in the meantime has imposed sanctions including a ban on package holidays, which could cost Turkey billions of dollars.

Adam Wilson, of Lostock Hall, was found with serious injuries at a property on Albrighton Crescent in Lostock Hall near Preston in September.
Jason Taylor, 21, of Westfield, Lostock Hall denied murder but was found guilty after a trial by jury.
At Preston Court, he was ordered to serve a minimum of 25 years.
Mr Wilson died as a result of catastrophic bleeding from a stab wound in his thigh, the Crown Prosecution Service (CPS) said.
Sophie Lorimer from the CPS North West said the "brutal attack" in front of his ex-partner was "purely motivated by jealousy".
"He could not accept that the relationship with his ex-girlfriend was over," she said.
Taylor's girlfriend said he bombarded her with text messages and phone calls which "progressively became more and more abusive".
"The final text he sent to her stated he was giving her one last chance before things turned sour.
"Minutes later he violently broke into her house where Adam Wilson was also present."
Ms Lorimer said Taylor then stabbed Mr Wilson numerous times with a large knife which he had taken with him.
Taylor carried out the "frenzied" knife attack "fully aware" there were two young children also present at the house, she said.
He then fled and hid from police in a neighbouring garden, she added.
Ms Lorimer said Taylor had shown "no remorse" throughout the case in which he claimed he was acting in self-defence.
Det Ch Insp Neil Ashton of Lancashire Police said Taylor's actions were carried out "in anger and jealousy".
He said: "His actions were completely unprecedented and resulted in the needless and very sad loss of a young man's life."
Data on the flight recorder of the Russian war plane downed by Turkey last month has so far proved to be unreadable, Russia's military has said.
[NEXT_CONCEPT]
A man who murdered a Lancashire man in a "jealous, frenzied knife attack" at his ex-partner's house has been jailed for life.