Mimi Macpherson was born as Miriam Frances Gow in Australia. Her older sister is the actress Elle Machapherson and she also has two younger siblings. Miriam changed her name to Mimi after Mimi Dickson, her mother's sister and a successful model. After Mimi's parents divorced, the family took the surname of her second husband, a lawyer named Neil Machpherson. Today, Mimi Macpherson is known for her whale activism.

It started when she was 21 years old and worked for a whale watching boat doing jobs like scrubbing toilets. When the whale watching business failed, Mimi decided to start her own business. She got a boat which was named "Matilda 2" and called her enterprise "Mimi Macpherson Whale Watch Expedition". She won an award for tourism which increased her business. Mimi was able to expand to have two more boats and received several other awards for tourism.

In addition to this, Mimi was awarded as "The Executive Woman of the Year" in 1997. Her ventures led her to get a job as a presenter on the Discovery Channel. Later on, in 2007, Mimi began to follow in her sister's footsteps. She signed onto a reality contest for singing called "It Takes Two". Mimi and her partner David Hobson came in third place.

This same year, Mimi MacPherson was part of a huge scandal when a sex tape of her and her boyfriend Michael Hellwig was leaked. She also was charged and convicted for driving under the influence of alcohol for the third time, the first two instances happening in 1995 and 2001. Mimi got a deal with "Evolve Make Up" in 2008 and became their new "face". However, the end of 2008 was bad for Mimi MacPherson and she declared bankruptcy.