Ruben Mills began school in the wheat-belt town of Salmon Gums, Western Australia. He constantly changed schools because his father worked for Westrail. Mills finished third year at Governor Stirling Senior High School in Midland and would have liked to go to university. His first jobs were carting bags of potatoes and stacking salt bags. The family moved to the town of Wickham in the north west and Mills began work at Robe River Iron. Following this he worked for Boral Cyclone, before getting a job with Austrack. He then started in his first position with the government in the Support Accommodation Assistance Program (SAAP) helping to combat domestic violence. He also coordinated sports programs and later worked for the Deparment of Social Security. Mills's father had been removed from his Punjima family as a child, and because of this Mills was chosen to be intiated in 1989.