Gu Hye Sun (Korean: 구혜선) is a South Korean popular actress and also a singer, who has recently gained fame in the hit drama, Pure in Heart (열 아홉 순정) as a starring role, Gukhwa and also sang the title song of it. Koo Hye Sun is well-known for portraying Geum Jan Di in KBS 2TV's drama Boys Over Flowers together with Lee Min Ho, Kim Hyun Joong, Kim Bum and Kim Joon. Goo Hye Sun also starred in many other roles.Besides being an actress, Koo Hye Sun has various other occupations such as MC-ing, being in music videos, and even showing her face to others by doing CFs. She is the cover model for Taiwan's Vogue Magazine July 2009.
Koo Hye Sun recently wrote a book, "Tango" (탱고) which is a love story focusing on one girl who falls in love with three men. The book received good reviews and many critics praised her for her well structured sentences. This book is currently a bestseller, selling 30,000 copies within one week.