King Narai Hospital (Thai: โรงพยาบาลพระนารายณ์มหาราช), is a hospital located in Mueang Lopburi district, Lopburi province, Thailand.

It is classified under the Ministry of Public Health as a general hospital.

It is a main teaching hospital for the Chulabhorn International College of Medicine, Thammasat University and an affiliated teaching hospital of the Faculty of Medicine, Srinakharinwirot University.

On 18 September 1979, King Bhumibol Adulyadej renamed the hospital as King Narai Hospital in commemoration of King Narai, a leading figure in the development of Lopburi during the Ayutthaya Kingdom.

It currently has a capacity of 550 beds and is a referral center for patients from Chai Nat, Ang Thong and Singburi provinces.