Xiao Yuan, 57, admitted stealing and selling 125 works of Art for more than 34million yuan (£3.5million), between 2004 and 2011.
The former chief librarian stole 143 paintings worth more than £10million from a university gallery in China, and replaced them with fakes he had painted himself.
Prosecutors estimate that the 18 paintings that he kept were worth more than 70 million yuan (£7.2million).
Yuan used the money from the thefts to buy apartments and other paintings.
Defending himself, Yuan claims that the practice was incredibly common in the library of the Guangzhou Academy of Fine Arts in south-east China, as he appeared in court today.
He claimed that he had already noticed fakes hanging in the gallery on his first day in the job, and that the handling of such paintings was insecure.
Incredibly, he claimed, someone else then stole the fakes that he had painted.
‘I realised someone else had replaced my paintings with their own because I could clearly discern that their works were terribly bad,’ Yuan told the Guangzhou People’s Intermediate Court.
He claimed that students and professors were able to borrow the invaluable paintings in the same way as library books, and that he had no idea who had replaced his fakes.