Ascham School is an independent, non-denominational, day and boarding school for girls, located in Edgecliff, an Eastern Suburb of Sydney, New South Wales, Australia.

Established in 1886, the school has a non-selective enrolment policy and currently has approximately 1000 students from Kindergarten to Year 12, including 100 boarders from Years 6 to 12.

Ascham follows the 'Dalton Plan', an educational philosophy created by Helen Parkhurst in 1916. The 'Dalton Plan' aims to produce independent and confident leaders.

Ascham is a member of the Alliance of Girls' Schools Australasia (AGSA), the Junior School Heads Association of Australia the Association of Heads of Independent Schools of Australia (AHISA), the Australian Boarding Schools' Association, and the Association of Heads of Independent Girls' Schools (AHIGS).

Ascham is operated as a not-for-profit company. All funds must be used to benefit the school. This function is administered by the school's Council of Governors who are elected by the school's members.