Background <p>Gastrointestinal manifestations are common in pediatric IgA vasculitis (IgAV), but their relationship with renal involvement remains incompletely understood. Early identification of children at risk for renal complications is clinically important.</p> Methods <p>We conducted a retrospective single-center cohort study including children diagnosed with IgA vasculitis between August 2023 and June 2024. Clinical characteristics, gastrointestinal manifestations, and renal outcomes were analyzed. Renal involvement was defined as hematuria and/or proteinuria by the end of follow-up, including both baseline and incident cases. Multivariable logistic regression was performed to identify factors associated with renal involvement. Sensitivity and subgroup analyses were conducted to assess the robustness of the findings.</p> Results <p>Sixty-eight children with IgA vasculitis were included, of whom 44 had available follow-up data. Gastrointestinal manifestations were observed in 82.4% of patients, and among these, 55.4% had severe involvement. Among patients with follow-up data, 19/44 (43.2%) had renal involvement by the end of follow-up, including 14 cases present at baseline and 5 new-onset cases. Severe gastrointestinal involvement was associated with renal involvement in multivariable analysis (adjusted OR 4.34, 95% CI 1.48–12.65, <i>p</i> = 0.007). In sensitivity and subgroup analyses, the direction of association was consistent, although statistical significance was not maintained.</p> Conclusions <p>Severe gastrointestinal involvement may be associated with an increased likelihood of early renal manifestations in pediatric IgA vasculitis. These findings suggest that closer renal monitoring may be warranted in patients presenting with severe gastrointestinal symptoms. Larger multicenter studies with longer follow-up are needed to confirm these observations.</p>