Park made her official debut as a member of After School under the stage name "Lizzy" when they released their third single "Bang!"

[8] In June 2010, Lizzy and her fellow After School members Raina and Nana formed a sub-unit named Orange Caramel and released their first mini-album featuring the lead single "Magic Girl".

[12] In the same month, Park joined Sistar's Bora, 4Minute's Gayoon, Secret's Sunhwa and Kara's Jiyoung to form the project girl group Mystic White for the 2012 SBS Gayo Daejun.

[13] In July 2013, Park made a cameo appearance in the Japanese horror drama Evil Spirit Ward, playing the role of a Korean foreign student named Tehi.

[16] Lizzy, G.NA, 4Minute's Kwon So-hyun and Kara's Heo Young-ji became a girl group called Chamsonyeo (참소녀) for the show.

[18] That same month, Park replaced Kim Sung-eun as a co-MC of the food variety show, Tasty Road.

[19] On January 23, 2015, Park debuted as a solo singer with the trot song "Not An Easy Girl" (쉬운 여자 아니에요).

[22] The song was written by Duble Sidekick, who said PMS (which usually means premenstrual syndrome) refers to "a monster that creates all the worries and stress suffered by a high school girl".

[28] On July 3 it was announced that Park had changed her promotional name from 'Lizzy' to 'Park Soo-ah',[4] and was cast in the web drama I Picked Up a Celebrity on the Street.

[34] In August 2021, Celltrion Entertainment announced that Park Soo-Ah's contract had expired, and after coming to an agreement between both parties, it would not be renewed.