Objective To analyze the characteristics of autoantibody expression and prognosis influencing factors in children with immune thrombocytopenia (ITP). Methods The clinical data of 299 children with newly diagnosed ITP hospitalized from September 2020 to September 2021 were retrospectively analyzed. Results A total of 299 children (171 boys and 128 girls) with ITP were included, and the median age was 2.7 (1.0-4.6) years. Among the 296 ITP children who completed autoantibody spectrum detection, 114 (38.5%) showed positive autoantibody spectrum expression. One hundred and fourteen patients (38.5%) of the 296 ITP children who finished autoantibody spectrum detection had positive autoantibody spectrum expression. Among them, 101 patients (88.6%) were positive for anti-nuclear antibody, 59 (51.8%) were positive for anti-SSA /RO52KD antibody, and 52 (45.6%) were positive for anti-SSA /RO60KD antibody. Of 299 children with ITP, 205 were cured. Compared with the cured group, the uncured group had a higher proportion of age ≥ 1 year old, positive antinuclear antibody, anti-SSA/RO52KD antibody, anti-SSA/RO60KD antibody and bleeding score≥3, and a lower proportion of preceding infection and gammaglobulin alone, with statistically significant differences (P<0.05). The binary logistics regression analysis showed that age ≥ 1 year old, positive antinuclear antibody, and bleeding score ≥ 3 were independent risk factors for ITP prognosis (P<0.05), and a history of preceding infection was an independent protective factor for ITP prognosis (P<0.05). Conclusions Autoantibody spectrum antibody expression is common in children with ITP. Age, history of preceding infection, antinuclear antibody and bleeding score are associated with ITP prognosis.