Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of August 10, 2026.

Dr. John Ilsun Ryu, OD

Individual provider Optometrist · NPI 1609946847

Dr. John Ilsun Ryu, OD is an Optometrist in Simi Valley, California. Practices as a sole proprietor. Licensed in California.

Licensed in
CA
In the registry since
2006
What do these letters mean?
OD — Doctor of Optometry
An optometrist: examines eyes, prescribes glasses and contacts, and treats many eye conditions.

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Practice location Address checks out

690 E Los Angeles Ave Ste A
Simi Valley, CA 93065-1857
Phone: (626) 376-3513
Fax: (905) 250-1001
Show map & directions

Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Optometrist (primary) Taxonomy 152W00000X · Licence 11209T (CA)

Record details

NPI number1609946847
Entity typeIndividual (Type 1)
GenderMale
Credentials OD
Sole proprietorYes
NPI enumeratedNovember 8, 2006
Last updated in NPPESJuly 15, 2024
Certification dateJuly 15, 2024
Mailing address1194 Knottingham St, Simi Valley, CA 93065-5167

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