Park Ha Sun was a student of Dongguk University's Theater and Film Department. In 2005, at the age of 19, she attended the screening of the movie "Daddy Longlegs" and was introduced to the industry by Ha Ji Won's manager. In 2005, she appeared in SBS drama "Love Needs a Miracle" and became famous. In 2006, director Ahn Byeong Ki's fourth horror film "APT" was her first official work on the big screen. In 2006, Park Ha Seon became one of the ambassadors of her alma mater Dongguk University's 100th anniversary celebration.