Jang Yoon Ju is a South Korean model, television personality, singer-songwriter and actress. Jang began modelling in 1997 when she was 17 years old, and became one of the most successful Korean fashion models, with a career spanning almost two decades. She also hosts "Korea's Next Top Model" and won "Best Radio DJ" at the 2013 KBS Entertainment Awards for KBS Cool FM's Rooftop Radio. As a singer-songwriter, Yoon Ju has released two albums, "Dream" and "I'm Fine". She made her acting debut in 2015, playing a detective in Ryoo Seung Wan's crime thriller "Veteran".
In May 2011, Yoon Ju along with fellow models Kim Jae Wook, Ji Hyun Jung, Han Hye Jin and Song Kyung Ah, co-authored a book titled "Top Model". It is based on their experiences in the industry and includes beauty, makeup and styling tips. She has also appeared in various variety shows including "Running Man" and "Infinite Challenge".