Mitsu Shoyama's mother was a teacher in Japan before the family moved to Kamloops, British Columbia, and encouraged her children to pursue education. Mitsu took that to heart, enrolling at Seattle University. When the war erupted, she was relocated to the nursing school in St. Boniface, Manitoba, and graduated from there in 1943.
In the mid 1940s, she moved to Toronto, Ontario, and worked as a general staff nurse in the surgery department of Toronto Western Hospital. She returned back to Kamloops and took staff nurse position at the Royal Inland Hospital. She had a successful career as head nurse in the emergency ward, operating room, recovery room and outpatient department until retirement in 1977.
She was an ardent advocate of ongoing education for nurses and had taken courses to keep up to the rapid progress being made in the medical field. With years of hands-on experience and education, she was able to envision a progressive and increasingly independent role for nurses in the field of health care. In 1986, she was given the Award of Honour by the College of Registered Nurses of British Columbia. She died in 2002.