OBJECTIVE: To study the correlation of plasma acylation-stimulating protein (ASP) with body mass index (BMI) and blood lipid in children with obesity. METHODS: Thirty children with simple obesity and 30 healthy children were involved in this study. Plasma ASP levels were determined using ELISA. Blood lipid levels were detected with fully automatic biochemical analyser by turbidimetry. RESULTS: The levels of plasma ASP ( 73.87± 24.04 g/L vs 39.47± 13.68 g/L), cholesterol ( 5.71± 0.61 mmol/L vs 4.29± 0.49 mmol/L), triglyceride ( 1.77± 0.30 mmol/L vs 1.02± 0.25 mmol/L) and apoprotein B ( 0.98± 0.20 mmol/L vs 0.85± 0.11 mmol/L) increased significantly in obese children compared to those in the healthy children (P< 0.01 or P< 0.05). ASP was positively correlated to BMI, triglyceride and cholesterol levels (r= 0.43, P< 0.05; r= 0.48, P< 0.05; r= 0.68, P< 0.01, respectively). The ASP levels were significantly higher in the obese children with family history of obesity than those in the obese children without ( 103.4± 10.57 g/L vs 71.15± 24.9 g/L, P< 0.01). CONCLUSIONS: Plasma ASP may be used as a marker for evaluating fat metabolism in children with obesity. It might be valuable in predicting the possibility of developing cardiovascular diseases in their later lives.