Objective <p>The aim of this study was to evaluate the relationship between serum fibrinogen, albumin, and D-dimer levels and clinical thrombosis factors in children with nephrotic syndrome (NS).</p> Method <p>This observational-analytical study compared clinical and laboratory data of 56 children (1–16 years) with NS who were hospitalized in the pediatric nephrology ward of hospital in 2023.</p> Results <p>The sample included 33 boys and 23 girls with a mean age of 6.3 years. Clinical thrombosis was identified in only 2 girls (3.6%). Moreover, elevated fibrinogen and D-dimer were found in 78.6% and 60.7% of the patients, respectively, without correlation with gender (<i>P</i> &gt; 0.05). Children with clinical thrombosis had significantly higher D-dimer levels (2224 ± 197.9 μg/L) than those without thrombosis (698.4 ± 818.08 μg/L; <i>P</i> = 0.01). Especially if the patient has nephrotic syndrome, D-dimer levels ≥ 2048.5 ng/ml may be a concern for clinical thrombosis. Conversely, no significant correlation was found between clinical thrombosis and albumin or fibrinogen levels (<i>P</i> &gt; 0.05). Higher levels of D-dimer (≥ 1000 ng/mL) correlated highly with fibrinogen levels ≥ 800 mg/dL (<i>P</i> = 0.038).</p> Conclusion <p>Elevated levels of D-dimer may serve as a predictor for clinical thrombosis in children with NS. Further large-scale studies are needed to determine other risk factors and poor prognosis predictors in children with NS.</p>