This article reports the clinical characteristics and treatment processes of three cases of mucormycosis occurring after hematopoietic stem cell transplantation in children, along with a review of relevant literature. All three patients presented with chest pain as the initial symptom, and metagenomic next-generation sequencing (mNGS) confirmed the mucycete infection early in all cases. Two patients recovered after treatment, while one succumbed to disseminated infection. mNGS has facilitated early diagnosis and treatment, reducing mortality rates. Additionally, surgical intervention is an important strategy for improving the prognosis of this condition.