Wan-in Koo, DO
Family Medicine
1101 Highway K
O'Fallon, MO 63366 Directions
4.7 out of 5
97 verified ratings
97 Ratings, 47 Comments
The following ratings and reviews are based on verified feedback collected from independently administered patient experience surveys. The ratings and comments submitted by patients reflect their own views and opinions. Patient identities are withheld to ensure confidentiality and privacy.
Oct 28, 2026
Wonderful doctor who truly cares for her patients.
Oct 27, 2026
A-PLUS
Oct 23, 2026
Great doctor
Oct 16, 2026
She’s very no nonsense which I typically like, but I feel rushed every time that I’m in there and she mentioned two things of concern right at the start of the appointment but then we never got back to the two things that were brought up
Oct 15, 2026
Dr. Koo, thank you for being my doctor and thank you to your staff for always making me feel like I matter!! You all are amazing!!
Oct 12, 2026
Dr Koo is an excellent physician, and I use SSM health services because of her.
Sep 29, 2026
She was nice and doing her job well.
Sep 19, 2026
No stone unturned, if you got something she will find it
Sep 5, 2026
She really is the best doctor I’ve had. I hope everyone can have a doctor like Dr. Koo. She knows her stuff and I never feel rushed or dismissed
Aug 25, 2026
Fantastic!
Aug 22, 2026
Dr.Koo is the best doctor, I have been going to her for many years, she listens and guides me through all the health issues.
Aug 21, 2026
Quick but not rushed. Kind, attentive and compassionate.
Aug 5, 2026
Dr Koo is so helpful and understanding
Aug 2, 2026
She is very thorough and patient with elderly patients.
Jul 27, 2026
Doctor Wan-In Koo is a woderful doctor. She is professional, knowledgeable, friendly and courteous.
Jul 15, 2026
Dr Koo is very good at her job.
Jul 13, 2026
Dr. Koo has been taking care of me for a long time. I wouldn't trade for another, she knows me so well.
Jun 26, 2026
Dr Koo is such a great doctor!
Jun 1, 2026
She took time to get to know you. She really cares about you.
May 23, 2026
Superb care
May 20, 2026
Dr Koo listens, explains and empathize. She is an exceptional doctor.
May 20, 2026
Very concerned
May 19, 2026
Very nice and good dr
May 13, 2026
Dr Koo is an amazing doctor who cares about her patients and does not make you feel rushed.
May 12, 2026
I can’t say it enough, she is the BEST!!!
May 8, 2026
Very kind and very thorough in treatment
May 1, 2026
I’m tired of being in pain.
Apr 25, 2026
I always appreciate and greatly value Dr Koo's professionalism, knowledge and treatment as a family physician/ MD. I always recommend her to anyone looking for a family physician.
Apr 24, 2026
She explained everything to me. Just fabulous
Apr 21, 2026
She is one of the best
Apr 12, 2026
Good
Feb 18, 2026
She always listens, then suggests possible options.
Jan 24, 2026
Caring and thorough
Jan 19, 2026
A great doctor!
Jan 18, 2026
Dr koo is very kind, knowledgeable and a great doctor.
Jan 16, 2026
Dr. Wan-In Koo was wonderful. I felt as if my concerns were intently listened to and addressed with care and thoughtful recommendations
Jan 14, 2026
I like doctor Koo , she’s always professional
Jan 4, 2026
Great
Jan 4, 2026
The Best !!!!!!!
Dec 30, 2025
Professional and Courteous
Dec 29, 2025
Good
Dec 23, 2025
She is extremely nice, attentive, and thorough in her examination and care. She goes above and beyond to ensure questions are answered.
Dec 12, 2025
Dr. Koo is the kindest, most intelligent, and the most caring doctor I have ever seen in my 69 years. She know my medical history and helps me make the best medical decisions I could make. She should be cloned!
Dec 2, 2025
Efficient and friendly
Dec 2, 2025
Dr. Koo is the best.
Dec 1, 2025
Dr. Koo is the best doctor. She listens patiently to all the issues and addresses them all ensuring that everything is being taken care off.
Nov 21, 2025
She did an awesome job 👏🏾.