Cao Youyin (曹又尹), formerly known as Cao Cheng (曹呈), is a Chinese pro 3 dan born 1987-02-16. She was promoted 1 dan in 2000, 2 dan in 2005 and 3 dan on 2009-07-30.
Winner, in 2007, of the 1st Women Xinrenwang championship.
Winner of the 2010 Chinese National Women Individual.
Winner of the 2011 Chinese National Women Individual (2011-09-25).
Winner of the 2013 Chinese National Women Individual