A jury took less than three hours to convict Alexander Pichushkin of the murders, most of which occurred over five years in a sprawling southern park. He was also found guilty of three attempted murders.
Judge Vladimir Usov read the verdict for one hour, while 33-year-old Pichushkin, standing inside a reinforced glass cage, leaned against the wall and stared at the floor.
The courthouse was packed with journalists and relatives of victims who had closely followed the five-week trial.
Prosecutors recommended the judge sentence Pichushkin to life imprisonment, with the first 15 years to be spent in isolation given the convicted man's violent nature. The judge has not yet set a date for sentencing.
Russia has imposed a moratorium on the death sentence but has not abolished it.
Most of Pichushkin's victims were killed in Bittsa Park, and the serial killer became known as the "Bittsa Maniac."
Pichushkin boasted of killing 63 people, one short of filling up the chessboard, but prosecutors were able to find evidence only for 48 murders.
At the cramped apartment where he shared a bedroom with his mother, police found his chessboard with numbers on its squares, all the way up to 62. He boasted he had nearly reached the last square, No. 64, by the time police captured him.
Prosecutors said Pichushkin lured his victims, many of them homeless, to the park by promising them vodka if they would join him in mourning the death of his dog.
They say he killed 11 people in 2001, including six in one month. He killed most of his victims by throwing them into a sewage pit after they were drunk, and in a few cases strangled or hit them in the head, prosecutors said.
Beginning in 2005, he began to kill with "particular cruelty," hitting his intoxicated victims multiple times in the head with a hammer, then sticking an unfinished bottle of vodka into their shattered skulls, prosecutors said. He also no longer tried to conceal the bodies.
Prosecutors said Monday that Pichushkin had admitted killing one of his last victims in February 2006 to demonstrate that he was still at large following inaccurate reports in Russian newspapers that the Bittsa Maniac had been caught.
Pichushkin was arrested in June 2006 after a woman left a note at home saying that she was going for a walk with him and was then found dead. Pichushkin said he was aware of the note but killed her anyway.
"I burned myself, so there's no need for the cops to take credit for catching me," he said during the trial. "I'm a professional."