Chromosome 6 abnormalities such as paternal uniparental isodisomy, paternal 6q24 duplication, and maternal DMR (differentially methylated region) hypomethylation are a common cause of transient neonatal diabetes mellitus (TNDM). Oral sulfonylurea (SU) is used off-label to treat permanent neonatal diabetes mellitus owing to potassium channel mutation but has not been evaluated in TNDM. Our objective was to evaluate the efficacy and safety of SU therapy in chromosome 6-related TNDM. Description of 3 case reports and literature review was the subject of the study. SU therapy was successful in 2 patients (initiated during neonatal life in 1 patient and during relapse in the other) but failed in the other despite the use of high dosage. The literature review identified 11 cases of patients with chromosome 6-related TNDM treated with SU, including 4 treated before remission and 7 after the relapse. SU therapy was consistently effective, although 4 patients treated after the relapse required multiple oral medications. None of the patients needed associated insulin therapy. No side effects of SU or complications of diabetes were reported. SU seems effective and safe in chromosome 6-related TNDM treatment when used to treat the initial episode of diabetes or the relapse. It improves patients' and families' quality of life. SU is available only as oral tablets. A pediatric dosage form would facilitate the treatment of neonates and infants.