Diana L. Maas, MD

Associate Professor
Accepting New Patients

Call for an appointment

New & Established Patients Call 414-777-7700
Call for an appointment
Accepting New Patients
Call for an appointment
New & Established Patients Call 414-777-7700

My philosophy of care is to take the time to educate patients about their medical condition so that they can share in the decision making processes of their care.

My philosophy of care is to take the time to educate patients about their medical condition so that they can share in the decision making processes of their care.


Dr. Maas has been involved in the specialty of Endocrinology, Diabetes and Metabolism since early 1990. She received her medical training and completed her residency and fellowship at the Medical College of Wisconsin and Affiliated Hospitals. Dr. Maas is an Associate Professor of Medicine and the Director of the Pituitary Clinic. She works with the neurosurgeons as a team to take care of patients with pituitary tumors.



Diseases & Conditions

Adrenal Disorders
Cushing's Syndrome
Parathyroid Disease
Pituitary Disorders
Thyroid Disease

Treatment & Services

Virtual Visit

Ages Seen


Languages Spoken


Hospital Affiliations

Froedtert Hospital


8750 William Coffey Dr.
Milwaukee, WI 53226
Endocrinology - Froedtert Hospital

Education & Training

Medical College of Wisconsin - Milwaukee - Doctor of Medicine - (1985)

Medical College of Wisconsin - Milwaukee - Residency in General Internal Medicine - (1985-1988)

Medical College of Wisconsin - Milwaukee - Fellowship in Endocrinology & Metabolism - (1988-1991)

Board Certifications

Endocrinology, Diabetes and Metabolism
Internal Medicine

Patient Reviews

The comments are submitted by patients (or their caregivers) and reflect their views and opinions. The comments are not endorsed by and do not necessarily reflect the views of the Froedtert & the Medical College of Wisconsin health network. Learn more about our survey.*


* Due to high volume, only the most recent 30 comments are displayed for a selected value.

Dr. Maas is simply the best! Besides being caring and professional, she diagnosed a condition that two other doctors missed. Froedtert is lucky to have her.
My experience was very favorable. Dr. Maas is always a pleasure, as she is very thorough and clear to understand.I would recommend Dr. Maas to anyone with an issue of a Petuitory issue.Dr. Maas prepared me for the surgery that I had in 2017.
Have been a patient of Dr Maas for over 21 years. Have always liked her care and those of her assistance/nurses.
Friendly professional and enjoyed our visit
Dr. Diana Maas and staff are great!
Dr Maas is an excellent doctor and had helped me very much. She is very easy to talk with and listens to what I have to say. I look forward to seeing her because I know she will help me and she always steers me in the right direction and gives good advice. I have never had a bad experience with any staff in this specialty clinic
Thank you for all the attention and hard work.
Dr. Diana Maas is the best doctor I have ever had. She is caring, supportive, and listens to you. She is the best.
Dr. Maas is an excellent physician!
Dr. Maas is always very professional while also being patient friendly. She gives 100% of her attention, never making me feel rushed.
Greatly appreciate the Kindness, Care and Expertise Dr. Maas and the Endocrine Group provide with each visit.
Dr Maas is outstanding in every way! She is the best!!!!'n
In addition to providing the care for which I came to her, Dr. Maas went well beyond that care, trying to assist me with recent issue unrelated to endocrinology, and did, to the best of her ability provide me with critical information that should have been provided to me through another practitioner at an entirely different clinic. Seeing Dr. Maas is always helpful, but this visit was particularly so.
Dr. Maas is the best!
Dr Maas is always very caring and easy to talk with.
I learned more about my visit reading the doctor notes after than during my examination
Dr. Maas is the one of the best doctors!
Always a pleasure to see Dr. Maas.
Dr. Maas is an outstanding doctor!
Dr. Maas is an excellent physician. She goes above and beyond for her patients.
Dr Maas is fantastic! It is always a pleasure seeing her. She is the best!!!!
Dr. Mass always in kind gentle and knowledgeable in her care. She is the reason I'm at Froedtert PERIOD
Dr. Maas is one of the best healthcare providers I have, and I always enjoy my appointments with her and come away well informed. I have recommended her to others with endocrine issues.
Dr. Maas has always been on top of my conditions and honestly takes the most thorough, specific, & helpful After-Visit Notes available on MyChart in comparison to my other doctors/departments I see (which includes neurology & neuro-ophthalmology) I trust & value her opinion and eye for detail, and hope to continue my care with her for years to come.
I feel very fortunate to work with Dr Maas. She is compassionate, very skilled, caring, and explains thing clearly. She really listens to me and answers my questions.
Dr. Maas is the best Dr. She is friendly, smart, and very understanding. I live in Florida but come to Froedtert because I believe she is the best person to take care of me.
Dr. Maas is the best.
My provider, Dr. Mass, is simply outstanding. She is through, involved and listens in depth to my concerns and issues.
I love the care Dr Diana Maas provided for me. She is a very kind, caring and compassionate physician and I would highly recommend her to others.
Dr. Maas has been my doctor for a long time. She has always taken the time to listen to me and answer my questions.
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