King's College London has received a development grant from the Department for Education to establish the school for sixth-form students, with plans for it to open in September 2014.
The school's creation is also aimed at increasing the number of young people with the right level of maths skills to study science, technology, engineering and maths subjects at highly selective universities.
"On the back of our existing reputation for research and teaching excellence in the field of mathematics, we are committed to extending our existing outreach activities with the aim of improving standards of maths education," said Rick Trainor, King's principal.
"Our new specialist school will provide vital support for sixth-formers in London to enable them to achieve their aspirations of studying STEM subjects - such as mathematics, physics, engineering and computer science - at leading universities."
Michael Gove, the education secretary, said the move was an "excellent example of a world-class higher education institution playing an active role in preparing gifted young people for the rigours of university study".
Under government plans, the new school, which will involve both King's College's department of mathematics and its department of education and professional studies, will be one of a number of university-sponsored mathematics schools for sixth-formers. Alison Wolf, Sir Roy Griffiths professor of public sector management at King's and author of the Wolf Review of Vocational Education, is to lead the school.
"We believe that we can make an important contribution to improving the levels of attainment of young people, who will go on to become the mathematicians, scientists and engineers of the future," Professor Trainor added.