Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum Sole proprietor

Dr. Mark K Li, M.D.

Internal Medicine Physician in Wheaton, MD · enumerated 2005 · practices at Mark K Li, MD.

Data current as of Jul 13, 2026 · sourced from CMS NPPES

National Provider Identifier

1356338032

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Registry record

Entity type Individual (Type 1)

Name Dr. Mark K Li

Credential M.D.

Sex Male

Practice address Wheaton, MD, 20902

Phone (301) 649-5151

Fax (301) 649-7368

Enumeration date Sep 29, 2005

Last updated in NPPES Apr 15, 2008

Street address withheld: NPPES sole-proprietor addresses can be home addresses. See our data policy.

Taxonomy & licenses

207R00000X Internal Medicine Physician Allopathic & Osteopathic Physicians · License D0027865 (MD) Primary

MD · Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD credential

Other identifiers

Identifier	Type	State	Issuer
85347	Other	-	ALLIANCE
3493546	Other	-	CIGNA
85347	Other	-	MDIPA
04960807	Medicaid	DC	-
110003971	Other	DC	RAILROAD MEDICARE
0075758	Other	-	AETNA HMO
4081271	Other	-	AETNA PPO
413303	Other	-	UNITED HEALTHCARE
37220001	Other	DC	CAREFIRST BCBS (NCA)
494439	Other	-	NCPPO
139301400	Medicaid	MD	-
27865	Other	-	ADVENTIST HEALTHCARE
4958MK	Other	MD	CAREFIRST BCBS (MARYLAND)
85347	Other	-	MAMSI
85347	Other	-	OPTIMUM CHOICE

What is an NPI number?

A National Provider Identifier (NPI) is a unique 10-digit number that CMS assigns to every U.S. healthcare provider and organization under HIPAA. Type 1 NPIs identify individual providers; Type 2 NPIs identify organizations. The NPI appears on insurance claims, prescriptions, and credentialing paperwork, and never changes, even if the provider moves or changes specialty.

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Frequently asked questions

What specialty is Mark Li?

Mark Li is registered in NPPES with the primary taxonomy of Internal Medicine Physician. The taxonomy code describes the provider's classification and area of specialization for claims and credentialing.

Is this the official NPI registry?

No. NPI Portal is a private site built on public CMS NPPES data. The official registry is npiregistry.cms.hhs.gov, operated by CMS.

Other providers at this practice address

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Mark K Li, MD Internal Medicine Physician · Wheaton, MD NPI 1730353855

Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2008-04-15.