A NSW policeman who allegedly sexually assaulted a nine-year-old girl on the state's Central Coast has been granted bail until his next court appearance in April.

The senior constable, attached to a local area command within the NSW Police Force Northern Region, did not enter pleas in Newcastle Local Court on Thursday to one count of sexual intercourse with a person aged under 10 and two counts of indecent assault of a person aged under 16.

The charges relate to an incident in 2009 in which the policeman allegedly sexually assaulted a girl on the Central Coast.

A NSW Police spokesperson said the 48-year-old had been suspended from active duty but remained on full pay.

The Professional Standards Command, responsible for setting standards for performance, conduct and integrity within the NSW Police Force, launched an investigation after receiving complaints last year about the alleged assault.

The man did not speak during Thursday's short hearing and had his bail continued until his next appearance in the same court on April 19.