To investigate the morphological and ultrastructural differences between normal and round-headed sperm and the outcomes of assisted reproduction in patients with partial globozoospermia.We collected clinical information and semen samples from 6 cases of partial globozoospermia confirmed in our hosptials from March 2023 to March 2024, performed Diff-Quik staining of the samples, observed the sperm morphology under the light microscope and transmission electron microscope, compared the ultrastructures between round-headed and normal spermatozoa, and analyzed the clinical outcomes of assisted reproduction in the patients.Under the light microscope, the the round-headed sperm had no acrosomal structure, some with tail abnormalities; while under the transmission electron microscope, they exhibited dissolved plasma membrane, acrosomal absence, small acrosomes, nucleoplasmic granulation, huge central vacuoles, swelling, absence or irregular arrangement of mitochondria in the neck, and disorganized or missed 9+2 microtubules in the tail. All the 6 patients underwent intracytoplasmic sperm injection (ICSI), and 1 of them achieved pregnancy.The sperm organelle is morphologically damaged and ultrastructurally abnormal in some patients with partial globozoospermia, which may be a key factor for their infertility, and ICSI can help some of them to achieve fertility.