OBJECTIVE To investigate the therapeutic effects of Supraglottoplasty (SGP) on newborns with severe laryngomalacia (LM) requiring respiratory support and to identify high-risk factors leading to treatment failure of SGP. METHODS Twenty-three newborns with severe LM requiring respiratory support, admitted to the Neonatology Department of Hunan children’s hospital from January 2016 to December 2020, were selected. Based on treatment outcomes, they were divided into a surgical success group (n=16) and a surgical failure group (n=7), The long-term prognosis of the successful group was followed up and the high-risk factors of the failed operation group were searched. RESULTS The data in this study showed a total of 23 surgeries were performed, with a surgical success rate of 69.6%. Preoperatively, 22 cases required invasive mechanical ventilation (95.65%), while 1 case required non-invasive ventilation (4.53%). In the surgical success group, respiratory difficulties disappeared within 12 months after birth, feeding difficulties resolved by 18 months, no recurrent respiratory infections occurred within 24 months after birth, and laryngeal stridor symptoms disappeared by 36 months after birth. In the surgical failure group, the mean age of mothers was 31.71±5.99 years, with 71.4% having asphyxia, 57.1% having heart disease, and 28.57% having genetic diseases. Compared with the surgical success group, the surgical failure group had older mothers, more comorbidities, and these differences were statistically significant (P<0.05). CONCLUSION SGP has a relatively high success rate for severe LM in newborns. Surgical failure is more common in cases with older mothers, concomitant perinatal asphyxia, congenital heart disease, genetic diseases, and other factors.