North Sydney Girls' High School (abbreviated as NSGHS, more commonly known as NSG) is a government-funded single-sex academically selective secondary day school for girls, located in Crows Nest, in Sydney, New South Wales, Australia.

Established in 1914, the school caters for approximately 910 students from Year 7 to Year 12. Admission to the school is based entirely on academic results through the Selective High Schools Test undertaken by students in Year 6.

In 2023, North Sydney Girls was ranked fourth among all high schools in Sydney.

In 2001, The Sun-Herald ranked North Sydney Girls High School first in Australia's top ten girls' schools, based on the number of its alumnae mentioned in the Who's Who in Australia. In 2022, North Sydney Girls High School ranked as the fourth high school in the state, based on the percentage of exams sat that achieved a Distinguished Achievers (DA).