Matthew Nienaber MD

Matthew Nienaber, D.O.

Internal Medicine

Not Accepting New Patients

About Matthew Nienaber, D.O. 

Born on the West Coast, native of the Bay Area, Matthew K. Nienaber, D.O., was raised in the Pacific Northwest with one foot in the sand and one in the water.  

Caring and compassionate, Dr. Nienaber works with his patients to provide individualized healthcare. With a strong passion for helping the underserved, he participates in medical missions to Africa, South America, and Mexico.  

Dr. Nienaber earned his medical degree at the Western University College of Osteopathic Medicine of the Pacific in Pomona, California. He completed his internship and residency at the Arrowhead Regional Medical Center in Colton, California.  

Dr. Nienaber’s patients say he is an excellent practitioner, is courteous and professional, and puts you at ease. They feel truly fortunate to have Dr. Nienaber as their primary physician.  

Dr. Nienaber is a former competitive dragon boat racer. He enjoys playing piano and bass, as well as restoring classic British race cars.  

I feel like my Doctor really cares about my health

Real Patient
Matthew Nienaber

Selected: Up Next:

Matthew K. Nienaber, D.O.
Family & Internal Medicine

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Family & Internal Medicine
01 / 02

Locations

1821 Wilshire Blvd., Suite 100,
Santa Monica, CA 90403
(310) 575-3100

Education

Medical School
Western University College of Osteopathic Medicine of the Pacific

Internship
Arrowhead Regional Medical Center, Colton, CA

Residency
Arrowhead Regional Medical Center, Colton, CA

Languages

Spanish

child checkup

Reviews

At Providence, we’re dedicated to providing you quality, personalized health care. We are constantly striving to optimize your experience.

As part of ensuring you have a positive experience with Providence, our online provider directory includes ratings and patient comments for select providers. More about our survey.

  • 5
  • 224 Reviews
  • 425 Comments
  • 5
02/25/2026

Dr Nienaber is very knowledgeable and easy to talk to. Highly recommend -thank you so much

Providence Patient
  • 5
02/19/2026

Dr Nienaber is the Best Dr I have beenToo

Providence Patient
  • 5
02/17/2026

My doctor is kind and empathetic .We talked about not only my healthcare,But my life in the universal sense as well;Mind , body and spirit.This , in my humble opinion, is the way all physicians should practice medicine.

Providence Patient
  • 5
02/08/2026

Dr. Nienabor provided excellent advice and service at a time in my life which was very trying. I cannot say enough about the excellent service and caring attitude he displayed.

Providence Patient
  • 5
02/01/2026

There are never any surprises, they are always very nice and professional about what they do. I have never been disappointed, and will recommend them to anyone.

Providence Patient
  • 5
02/01/2026

DrNienaber, treated in a way that was more than just a patient. He really took his time with me.

Providence Patient
  • 5
01/27/2026

Top notch provider. Really gives you focused attention. Knows your background and provides genuine care.

Providence Patient
  • 5
01/23/2026

The provider has been absolutely perfect in all matters concerning my rather complicated health issues. I couldn't ask for better.

Providence Patient
  • 5
01/23/2026

He takes time to discuss everything. He is very knowledgeable. He has a very friendly and outgoing manner.

Providence Patient
  • 5
01/15/2026

The greatest staff and doctor ever !

Providence Patient