Children with disabilities suffer disproportionately from the learning crisis. Although they represent only about 1.5% to 5% of the child population, they comprise more than half of out-of-school children globally. Inspired by a commitment that every child has the right to quality education, a growing global drive for inclusive education promotes an education system where children with disabilities receive an appropriate and high-quality education that is delivered alongside their peers. The global commitment to inclusive education is captured in the Sustainable Development Goal 4—ensuring inclusive and equitable education and promoting lifelong learning opportunities for all. This paper explores inclusive education for children with disabilities in Mongolia’s mainstream education system, based on a 2019 survey of more than 5,000 households; interviews with teachers, school administrators, education ministry officials, and social workers; and visits to schools and kindergartens in four provinces and one district of the capital city. Mongolia has developed a strong legal and policy framework for inclusive education aligned with international best practice, but implementation and capacity are lagging. This is illustrated using four indicators of inclusive education: inclusive culture, inclusive policies, inclusive practices, and inclusive physical environments. The conclusion presents a matrix of recommendations for government and education sector development partners.