Dennis Michael O’Connor, M.D. Fortified with the Sacrament of the Holy Mother Church on Tuesday, February 3, 2026. Born on June 8, 1942 to the late Edward Jeremiah O’Connor and Emma Theresa O’Connor (née Mueller). He is survived by his teenage sweetheart and beloved wife of 61 years, Beatrice O’Connor (née Giuliani); sons Patrick (Kathryn), Michael (Deborah), and Bryan (Alyssa); grandchildren Sean, Tommy, Nick, Maura, Sarah, and Nora; brothers Dan and Robert; nieces, nephews, and cherished friends.
Dr. O’Connor graduated from St Louis University High School and St Louis University Medical School. He joined the Cardinal Glennon Children’s Hospital medical staff in 1964 as a medical student and then as the hospital’s seventh full time pediatrician, where he spent more than five decades, aside from a two-year military assignment to the Centers for Disease Control. He was triple-board certified in Pediatrics, Pediatric Hematology-Oncology, and Pediatric Infectious Diseases.
During his tenure at Cardinal Glennon, Dr. O’Connor served in many roles. These included director of student and residency programs, interim chairperson of Pediatrics, Vice President of Medical affairs, and Medical Director of the Footprints Palliative Care Program, which was one of the first pediatric palliative care programs in the United States. The Dr. Dennis O’Connor Chair of Palliative Care was established at St. Louis University in his honor. Guided by his strong faith, he believed deeply in helping children and their families receive the best medical care paired with the best quality of life care.
Dr. O’Connor also served as a member of the Cardinal Glennon Children’s Foundation Board of Governors from 2012 to 2023. He was honored to be selected as the recipient of the Dr. Peter Danis Award for Lifetime Achievement in 2015, and the prestigious Glennon Award in 2019.
Outside of his work as a physician, Dr. O’Connor served on the Garden District Commission, dedicated to helping transform the neighborhood around Cardinal Glennon. He was a member and former President of the Board for Vision for Children at Risk, which focuses on the welfare of children in the St. Louis community. He extended his care and compassion to everyone he met, from patients and their families, to friends and neighbors. He was a patient teacher and was always willing to lend a cheerful hand.
Dennis was frequently found walking his long-time St. Louis Hills neighborhood, cycling the city, maintaining his beautiful home and gardens, keeping the neighborhood birds well fed, and repairing his collection of antique clocks. As an avid cyclist, he once estimated that he had ridden over 100,000 miles, including completing the 700 Miles to Hope ride to benefit The Matthew and Andrew Akin Foundation in 2016, and a ride with cycling legend, Greg LeMond.
Dennis’ greatest joys came from serving children and their families, teaching the doctors of the future, and being with his family, of whom he was immensely proud. He touched many lives with his kindness, skill, and faith, and will be greatly and forever missed by all who knew him.
All services are private including interment at Resurrection Cemetery. In lieu of flowers, donations may be made to his long-time parish, St. Raphael the Archangel, 6047 Bishops Place, 63109.
Long time friend of his Brother Bert
Besides being a great doctor caring and generous to all, a really good man. Will be sorely missed
Dennis helped save my daughter’s vision at Cardinal Glennon. Rest in peace in heaven!
Dennis was a delightfully cheerful, wise,
and cherished colleague, quick with a kind word or amusing story. A true doctor’s doctor. We fondly remember our many years of working with Dennis- he will be greatly missed by us all.
YOU were TOP OF MY LIST of Doctors I ever knew or worked with! I compared everyone to YOU! GOD knew YOU well Denny- so, I CAN ONLY IMAGINE 🎶🎶 the JOY & GIFT you are bringing to the HEAVENLY BANQUET! My sympathy to your family… what a loss for them! GOD blessed all if us with YOU!
He was the best attending physician we ever had the pleasure to learn from. He was an one-of-a-kind human being who made Cardinal Glennon and SLU a real clinicians institution. A life well lived.
To all my dear classmates and those missing and not with us. Denny was an inspiration to me as a fellow pediatrician and all others in our profession. I remember his excellent talk at a Pediatric Review meeting in the Ozarks years ago. He shared w us his experiences w cancer patients that were finally beyond remission despite all the efforts of the care team. He discussed the emptiness the families experienced entering in the child’s bedroom that brought all of us to near tears. And being a brilliant student of literature and history he quoted from Shakespeare’s play summarizing the emotions of those moments.
We are all the better for having known Denny. Thank you Michael Rolfing for “keeping us together”.
Jim Nusrala
Corvallis, OR
I’m so sad to hear of this news. Dr. O’Connor or “Uncle Dennis” to me was an amazingly talented and gifted human being. His kindness radiated. I will make sure to keep his memory alive and do good works in his name. Will miss him terribly.
Dr. O’Connor was a gift to our world.
Dennis O’Connor was a saint for our times. He lived a life of service, combined with humility and cheerfulness. He exuded goodness and intelligence, and it was a pleasure to be in his company. I hope Bea and the “boys” will share many happy memories as they adjust to life without him.
An amazing gentleman, outstanding pediatrician, dear colleague ! Dennis will be missed. Condolences to his family.
Dr Denny O’Connor embodied all that is kind and compassionate. I have worked with many physicians, in many different environments, over the years Dr O’Connor is a total standout as a practitioner, a teacher and a human being He touched so many more lives than he ever knew, including mine . We were blessed to have had him in our world.
My deepest condolonces to the family.
If the measure of a man is his contribution to the well being of others, Dennis O’Connor was a giant.
Dennis was an encourager! He lifted us with positive words and genuine interest in our progress. He was truly an inspiration and I was so blessed to have worked with him at Cardinal Glennon.
It was a privilege, an honor and a great pleasure to work with Dennis and to call him a friend. He made our great Glennon Family greater and kinder every day. Deepest sympathy to Bea and his family.
Dennis cast a broad shadow, that is certain. He impacted so many lives in so many ways. Of course his patients benefitted not only from his enormous intellect and unlimited compassion but perhaps more importantly from his down to earth practicality and common sense. Dennis was a superb role model for everyone in the Medical Center…the students, nurses, residents, attendings, faculty, administrators, chairmen and even the Deans were all better off with his influence. I am so much a better person to have shared my time with him as a colleague and friend. Sincere condolences to Bea and his family. May there be joy in the memories.
Honored to have met this great man, and to have spent much time with his son and his grandchildren, whose spirits clearly reflect his.
Seems like I always knew him.
Their home was right across the alley from ours
Always a great friend.
I am shedding tears and my memory bank is full of the fun we had growing up together.
Dennis, I’m so grateful that I got to share this planet & Cardinal Glennon with you. You left a trail of Hope & Kindness to everyone that passed your way. Thanks for making this world a better place. 😇
Marge Seidl