Runga was born in
Christchurch. Her mother, Sophia Tang, was a
Chinese Malaysian lounge singer in
Malaysia when she met Joseph Runga, a
Māori soldier on leave from
Vietnam. They both moved to New Zealand to live.
Runga grew up in
Hornby, Christchurch surrounded by a musically-inclined family, and started recording songs with her sisters,
Boh and Pearl, when she was only four years old. Runga's older sister Boh is now a vocalist in the New Zealand rock group
Stellar*, while Pearl is a session singer.
She learned how to play
drums at the age of eleven, and
guitar at about fourteen. Runga also learnt to play the
keyboard at around this time. She attended
Cashmere High School, joining high school bands and performing with local
jazz groups by her mid-teens.