Pesantren and Education of Nationality: Study Against al-Difâ‘ ‘ani al Wathân min Ahammi al-Wâjibât ‘ala Kulli Wâhidin Minnâ by Kiai Muhammad Said. Radical group often attacks against Islamic organizations that disagree with them, including pesantren. The understanding of pesantren with radical groups in the concept of nationality is contradictory. Radical group is anti nationalism, while pesantren is very close with nationalism. In this case, Pesantren Lirboyo has a book entitled al-Difâ‘ ‘ani al Wathân min Ahammi al-Wâjibât ‘ala Kulli Wâhidin Minnâ. This paper is the result of a research on the concept, application, and urgency of nationality education in the book of al-Difâ‘. Based on the research, the concept of nationality education is the media to maintain the unity of the Unitary State of the Republic of Indonesia. The application of nationality education is applying the rules of nationality education, namely strengthening unity, strengthening security, upholding benefits, and instilling a sense of loving the homeland.