St. Xavier's School was the first academic institution established by the Society of Jesus (Jesuits) in Nepal in 1951. Currently, it consists of student cohorts in twelve levels of study (Grades 1 to 12) and operates an elementary school, a middle school, and a high school under a single administration. One of the oldest private schools in the country, St. Xavier's has historically been considered an elite institution, often attracting students from the upper crust of Nepal's society. The school's alumni have traditionally occupied high ranking positions within the government, bureaucracy, military or distinguished themselves nationally in other professions.
St. Xavier's School was established by the Jesuit missionary Marshall D. Moran. Fresh from the newly acquired democratic political system after a century long system of familial rule by the "Ranas", Nepal was beginning to open out to the world and the incumbent king of Nepal, Tribhuwan Bir Bikram Shah, is said to have personally invited Moran, who at that time worked in Patna, India, to institute Jesuit education to Nepal. Moran complied and in 1951 St. Xavier's School was opened in Godawari, on the outskirts of the capital city Kathmandu.
St. Xavier's School was the first institute in Nepal to be affiliated with Cambridge University. In 1957 it offered the first GCE exams in Nepal and again in 1984 when the school resumed General Certificate of Education O levels. The early 1950s found Nepal isolated and little exposed to the outside world. St. Xavier's, run mostly by American Jesuits, introduced a new standard of excellence for education in Nepal.
While the mission statement of the school speaks of "formation of our students, their parents and each other, educational excellence, spiritual growth and social justice, active service of god, Nepal and the human society, its impact on the country is equally noticeable in the improvement of English taught at schools.
An all-boys school from 1951 until 2000, St. Xavier's began admitting girls starting with the academic session of 2000/01.
St. Xavier's School, established at Godawari on the outskirts of Kathmandu in 1951, added a branch at Jawalakhel within the city in 1954. Until 1999 the two branches operated as a single unit with students at Godawari transferring to Jawalakhel after grade six. The Jawalakhel branch on the other hand ran classes from grade one through grade ten. Starting in 1999 the Godawari branch extended its offerings beyond middle school to grade ten and became more of a local school, serving Godawari and surrounding areas. Jawalakhel draws students nationwide.
The school follows the national standard School Leaving Certificate (S.L.C.) curriculum for grade ten. The performance in the S.L.C. examinations by the students of St. Xavier's School has over the years been exceptional: failures in any given year are rare and well over half of all candidates score within the highest division (above an aggregate score of 60%).