<![CDATA[Abstrak Non-Suicidal Self Injury (NSSI) merupakan perilaku merusak diri tanpa intensi bunuh diri yang semakin menjadi perhatian serius dalam kesehatan mental, khususnya pada dewasa awal. Kesulitan regulasi emosi menjadi faktor risiko utama munculnya NSSI, di mana individu menggunakan perilaku melukai diri sebagai mekanisme koping maladaptif untuk melampiaskan emosi terpendam. Penelitian ini bertujuan menguji pengaruh Acceptance and Commitment Therapy (ACT) dalam meningkatkan regulasi emosi pada individu dewasa awal yang melakukan NSSI. Penelitian menggunakan desain quasi experimental one group pretest-posttest dengan tiga partisipan perempuan berusia 19-25 tahun yang dipilih melalui purposive sampling. Pengukuran regulasi emosi menggunakan Difficulties in Emotion Regulation Scale-Short Form (DERS-SF) yang diberikan sebelum dan sesudah enam sesi intervensi ACT. Hasil uji Paired Sample T-Test menunjukkan perbedaan signifikan tingkat regulasi emosi sebelum dan sesudah intervensi. Penurunan skor disregulasi emosi mencapai 45,4% dengan kategori pengaruh moderat. Nilai N-Gain sebesar 60,2% menunjukkan efektivitas cukup baik. Temuan mengindikasikan ACT efektif meningkatkan regulasi emosi melalui pengembangan fleksibilitas psikologis pada individu dewasa awal dengan NSSI, memberikan implikasi praktis bagi intervensi berbasis bukti dalam penanganan NSSI. Kata Kunci: Regulasi Emosi, Acceptance and Commitment Therapy, Non-Suicidal Self-Injury AbstractNon-Suicidal Self-Injury (NSSI) represents self-damaging behavior without suicidal intent that has become a serious concern in mental health, particularly among emerging adults. Emotion regulation difficulties constitute a primary risk factor for NSSI emergence, where individuals employ self-injurious behaviors as maladaptive coping mechanisms to release suppressed emotions. This study aimed to examine the effect of Acceptance and Commitment Therapy (ACT) on enhancing emotion regulation among emerging adults engaging in NSSI. The research employed a quasi-experimental one-group pretest-posttest design with three female participants aged 19-25 years selected through purposive sampling. Emotion regulation was measured using the Difficulties in Emotion Regulation Scale-Short Form (DERS-SF) administered before and after six ACT intervention sessions. Paired Sample T-Test results demonstrated significant differences in emotion regulation levels before and after intervention. Emotion dysregulation scores decreased by 45.4% with moderate effect size. N-Gain value of 60.2% indicated reasonably good effectiveness. Findings suggest ACT effectively enhances emotion regulation through psychological flexibility development in emerging adults with NSSI, providing practical implications for evidence-based interventions in NSSI management. Keywords: Emotion Regulation, Acceptance and Commitment Therapy, Non-Suicidal Self-Injury]]>
