The National Institute of Open Schooling was started as a project on Open Schooling under Central Board of Secondary Education (CBSE) in 1978. It was established in 1989 as National Open School (NOS) by the Govt of India, Ministry of Human Resource Development (MHRD). In 1990, NOS was vested with the authority to examine and certify learners registered with it up to Pre-Degree level Courses. It was re-christened as National Institute of Open Schooling (NIOS) in July 2002.

The National Institute of Open Schooling – NIOS was established in 1989 by Ministry of Human Resource Development; Government of India, to caters to the educational needs of the children out of school, school drop-outs and socially and economical backward section of the learner population.

Today, it is one of the largest Open Schooling systems in the world, with approximately 1, 500 000 students on its roll. The institute mission is to reach all by breaking all the physical, mental, economical or geographical or any other