Abstrak This study aims to prove the influence of the quality of friendship (stimulating friendship, help, intimacy, reliable alliances, self-validation, and emotional security) and subjective well-being (cognitive and affective aspects) on the characteristics of santri in the Islamic Boarding School of Al Amanah Al Gontory Pesantren. This research uses quantitative with multiple regression analysis method. The winning sample is 240 santri. The instrument collects data using a scale compiled by the author based on hardiness theory by Kobasa (1982), friendship quality theory by Mendelson and Aboud (2012), and subjective wellness theory by Diener, Lucas, and Oishi (2002). The results showed that there were significant differences in the quality of friendship and subjective well-being of santri of the Islamic Boarding School of Al Amanah Al Gontory Pesantren. Abstrak Penelitian ini bertujuan untuk membuktikan pengaruh quality of friendship (stimulating companionship, help, intimacy, reliable alliance, self validation, dan emotional security) dan subjective well being (aspek kognitif dan aspek afektif) terhadap hardiness santri Pondok Pesantren Al Amanah Al Gontory. Penelitian ini menggunakan pendekatan kuantitatif dengan metode analisis regresi berganda. Sampel berjumlah 240 santri. Instrumen pengumpulan data menggunakan skala yang disusun sendiri oleh penulis berdasarkan teori hardiness oleh Kobasa (1982), teori quality of friendship oleh Mendelson dan Aboud (2012), dan teori subjective well being oleh Diener, Lucas dan Oishi (2002). Hasil penelitian menunjukkan bahwa terdapat pengaruh yang signifikan quality of friendship dan subjective well being terhadap hardiness santri Pondok Pesantren Al Amanah Al Gontory.