Hindustani Prachar Sabha was founded by Mahatma Gandhi on 5 May 1942 at Wardha during the height of India's freedom movement. Gandhi envisioned a common language—a blend of simple Hindi and simple Urdu—that could unite the diverse linguistic and cultural communities of the country. Established to realize this vision, the Sabha has worked continuously to promote Hindustani while strengthening national integration, communal harmony, and mutual understanding.

From its inception, the institution received the support of eminent national leaders, including Jawaharlal Nehru, Dr. Zakir Husain, Kakasaheb Kalelkar, Balasaheb Kher, Shrimann Narayan Agrawal, and Morarji Desai. Perinben Captain and Goshiben Captain, granddaughters of Dadabhai Naoroji, devoted their lives to the growth of the Sabha. With the support of Jawaharlal Nehru, the Mahatma Gandhi Memorial Building was constructed at Charni Road, Mumbai, which continues to serve as the headquarters of the institution.

Hindustani Prachar Sabha also undertakes significant publishing and educational activities. It publishes books in both Hindi and Urdu and brings out the bilingual literary and research journal Hindustani Zaban, which reflects the shared linguistic and literary heritage of the two languages. The institution also maintains the Mahatma Gandhi Memorial Library, housing a valuable collection of books on Hindi, Urdu, and Hindustani language and literature, serving as an important resource for students, scholars, and literary enthusiasts.