Xu Demei (Chinese: ???; born May 23, 1967 in Zhejiang) is a former track and field athlete from PR China, who competed for her native country in the women's javelin throw event at the 1992 Summer Olympics in Barcelona, Spain.
Her biggest success was winning the world title in 1991, a week after China's first ever gold medal at the World Championships in Athletics by shot putter Huang Zhihong.
She was also Asian champion at the 1991 Asian Athletics Championships and won silver medals at the 1989 Asian Athletics Championships and 1990 Asian Games.