Tju was born in Southern California. Her sister is named Brianne Tju.
In 2021, Tju took a hiatus from physical acting to focus on her mental health.
Her first appearance on television was a commercial for Pizza Hut, while her first TV show performance was a part in Hannah Montana, at the age of seven.
Her first prominent role was as a voice actor in the children's animated series Monsters vs. Aliens, as the character of Sqweep. Next, Tju landed her first leading role in the Nickelodeon television special, The Massively Mixed Up Middle School Mystery, playing one of three young detectives.
↑Tju, Haley. Get to Know Me(English). Archived from the original on 2022-04-22. Retrieved on 2022-04-22. “I started my career at the young age of four in the film and TV industry and continued my acting journey until 2021. That’s when I decided to put my acting career on hold to fully pursue my other passions.”
↑Ojidu, Mary (February 8, 2022). In conversation with Haley Tju(English) (Interview). ÁJÍFA. Archived from the original on 2022-04-22. Retrieved on 2022-04-22. “HT: I’m still on a sort of break, although I do a lot of voiceover acting now. With on-screen acting, I need to heal within myself before I go back to that again.”