Frederick Norton Manning (25 February 1839 – 18 June 1903),[1] was a medical practitioner, military surgeon, Inspector General of the Insane for the Colony of New South Wales, and was an Australian Lunatic Asylum Superintendent.

Before accepting, Manning went overseas and studied methods of patient care and administration of asylums; on his return to Sydney he submitted a notable report.

He was appointed to Tarban Creek on 15 October 1868 and immediately reported on the isolation of patients from their relations in accommodation best described as 'prison-like and gloomy', the inadequate facilities for their gainful employment and recreation and the monotonous diets deficient in both quantity and quality.

In January 1869 the asylum's name was changed to the Hospital for the Insane, Gladesville, wherein patients were to receive treatment rather than be confined in a 'cemetery for diseased intellects'.

[1] Manning had become a trustee of Royal Prince Alfred Hospital in 1873 and was a member of the New South Wales branch of the British Medical Association.

Unmarried, he died from a stomach ulcer on 18 June 1903 at his rooms in Phillip Street, and at his request was buried in the cemetery at Gladesville Mental Hospital.