Background: Serum Cholinesterase (CHE) levels have been found to be elevated in individuals with nephrotic syndrome (NS); nevertheless, it is unknown whether CHE can serve as a biomarker for NS diagnosis and what its diagnostic relevance is for NS in minors. Methods: In this study, 138 minors aged 1-17 years with NS were enrolled, including 101 patients with the first episode of NS and 37 patients with relapsing NS. One hundred and four minors suffering from nephritis and 109 healthy minors were included as control groups. The clinical information and laboratory data of all NS patients and the control group were obtained. Logistic regression, correlation analyses and receiver operator characteristic curve were used to examine the value of CHE for NS patients. Results: Compared to patients diagnosed with nephritis and healthy minors in the control group, the serum CHE levels of total/first episode/relapsing NS patients were substantially higher (P < 0.05). The CHE was an independent risk predictor of total (adjusted odds ratio [OR] = 2.23, 95% confidence interval [CI]: 1.57-3.18)/first episode (adjusted OR = 4.02, 95% CI: 1.47-11.08)/relapsing (adjusted OR = 2.04, 95% CI: 1.42-2.93) NS, and was positively correlated with total cholesterol in total/first episode/relapsing NS patients, respectively. The optimal cutoff for total/first episode/relapsing NS all was 11 KU/L, but the diagnostic accuracy in first episode NS (area under the curve [AUC] = 0.96, 95% CI: 0.94-0.98) was higher than the total NS (AUC = 0.93, 95% CI: 0.91-0.96) and relapsing NS (AUC = 0.85, 95% CI: 0.78-0.92). Conclusion: CHE is a possible biomarker for NS and has good diagnostic accuracy for NS in minors, particularly for the first episode of NS in minors.