Yeo began acting while in high school. She continued to act while attending Korea University, where she studied literature.[2] She became known for her work in Daehakgeuk, which is also called the amateur student theater, during the 1950s and 1960s, alongside other contemporary Korean actors like Lee Soon-jae.[2][3]
She made her professional theater debut with a theater troupe in 1962.[2] From theater, she was able to transition to a successful television career.[2] She often played the role of a grandmother or "grandmotherly figure".[2] Examples of these characters included her roles in Toji in 1986 and Jewel in the Palace in 2003.[2]
Ms. Yeo was diagnosed with kidney cancer in 2007 while shooting the SBS TV series The King and I.[2] But she continued to act and began work on the KBS2 production of Love and Obsession,[2] eventually quitting the production due to pneumonia, indicating the spread of cancer to her lungs.[2]