The 25-year-old, who hails from Dunedin, would have gone into the Olympics as one of New Zealand's favourites for a gold medal after claiming the world title along with Jackie Kiddle in 2019.
"Sport at an elite level can be very challenging, and my own mental well-being, and the mental wellbeing of others will remain a focus of mine," McBride said in a release.
"I hope to offer support and guidance in this area to younger athletes in the near future.
''Representing New Zealand has been an absolute honour, and whilst the decision to retire was difficult, it has given me an opportunity to reflect on all that rowing has provided me with. I am very proud of what I have achieved in sport, and I look forward to the next stage of my life.''
McBride won three world titles in her career with back-to-back successes in the light-weight single sculls in 2015 and 2016.
She then claimed a silver in the double sculls with Kiddle before the duo won the world title in Ottensheim, Austria in 2019.
Rowing NZ High Performance Coach James Coote praised McBride's nine-year international career.
"Zoë has had an outstanding career at all levels in our sport, and she has made a courageous decision to retire as a world champion. Jackie Kiddle (fellow World Champion in the lightweight women's double) and I support her decision and look forward to seeing her succeed in her future endeavours."
"Zoë has been a considerably driven and resilient athlete, and it has been a privilege and pleasure to coach her at both an U23 and elite level.
"Seeing Zoë and Jackie cross the line in Linz 2019 will remain a personal highlight for me. While injuries and postponements have played their part in her career, Zoë has continued to overcome obstacles, and her determination and competitive spirit will always serve her well."
Throughout her rowing career McBride has completed a degree in marketing and qualifications in yoga training and nutrition.
She will remain based in Cambridge to pursue her career in marketing with a focus on women's health.
Kiddle will continue training at Lake Karapiro as part of Rowing NZ's High Performance Programme.
