Li Yajun was born in Beijing, China, in 1951, where she spent her childhood. She recalls loving art from the very youngest age and, when in kindergarten, her painting was selected to participate in "The World Children Painting Exhibition", which encouraged her and her family and increased her interest in the artistic world.
She was educated at the most famous art academy in China, the China Central Academy of Fine Arts, where she received strict professional training in various artistic fields including engraving, oil painting, illustration, binding and design. She received further training at the Tianjin Academy of Art.
Li Yajun describes her work as appearing to be drawn by a man rather than a woman. She emphasises her straightforward composition, bold and unconstrained lines, warm tone and vigorous brushwork. Her watercolours are a combination of reality and imagination, partially deriving from traditional Chinese painting, which mixes the styles of fine brushwork, drawing and sketching.
Since the late 1970s she has participated in many nationwide exhibitions in China, where she is a member of the China Artists Association.