Rapley started her musical career in 1987 singing with Upper Hutt Posse. In 1988 they released the first Aotearoa rap record and video ‘E Tu’ on Jayrem Records. In 1989 the Posse released the first Aotearoa Rap album Against the Flow on Southside Records.

In 1990 the Posse travelled to Sydney and opened for the Mad Professor and Bhundu Boys at Selina’s, Coogee Bay. While in Sydney they also recorded a Live to Air at Triple J, where ‘Do It Like This’ had received airplay.

The same year Teremoana travelled to the USA with UHP and played the Nation of Islam Stop the Killing cultural exchange concert in Detroit and they performed at the Detroit nightclub Latin Quarters with Rakim, Doug E Fresh and Flava Flav.

In 1990 Teremoana joined Moana and the Moahunters but she continued to perform with Upper Hutt Posse. In 1992 she travelled with the Moahunters to the New Orleans Jazz and Heritage Festival where they received a musical welcome at the airport from members of the Neville Brothers.

In 1995 she embarked on a solo career at the age of 24. Rapley has been a regular face in television broadcasting and advertising campaigns. She has also regularly spoken at education courses, universities and conferences, and served as a judge at live and televised talent shows. 

Either working solo or with other groups, she has toured New Zealand, Australia, America, Samoa, Canada, Fiji, Rarotonga, the UK and Europe. Over the course of her career she has toured with, opened for, and played alongside the likes of Billy TK, Herbs, Public Enemy, UB40, The Neville Brothers, MC Hammer, De La Soul, Ice T, Janet Jackson, M People, The Mint Chicks, Talib Kweli, The Fugees, Ben Harper and others. She also regularly performs at festivals both in New Zealand and abroad.

Between her collaborations with other artists and solo releases, Rapley's music has been released via Deepgrooves, Southside Records, Reprise Records, Eternal, Wea Records, Tangata, Kog Transmissions, Universal Jazz, Festival Mushroom, Bounce Records, Loop Recordings Aot(ear)oa, BMG and Sony.

Between 2000 and 2001 Rapley wrote for Selector Magazine. During this time she interviewed Ben Harper, Destiny’s Child, Aaliyah and Michael Franti.

Rapley's partner is Bill Urale, better known as rapper King Kapisi, they have four children together. In 2007 she started touring in King Kapisi's live band P.O.O.R. 

In 2021 Teremoana Rapley was appointed a Member of the New Zealand Order of Merit in the Queen’s Birthday Honours for services to music and television.

On August 29, 2024, Teremoana was honoured at the 20th Pacific Music Awards, with the Lifetime Achievement Award in recognition of her more than three decades as an artist, musician, television presenter, and producer.