OBJECTIVE: To study serum acylation-stimulating protein (ASP) and complement 3 (C3) levels and their relationship with blood lipids in children with primary nephrotic syndrome (PNS). METHODS: Blood samples were obtained from 35 PNS children with proteinuria, 25 children with PNS at remission and 35 body mass index-matched healthy children (control group). Fasting serum ASP, C3, albumin and blood lipids were measured. RESULTS: The serum ASP levels in the proteinuria group (101±22 nmol/L) were significantly higher than those in the remission group (32±8 nmol/L) and the control group (33± 8 nmol/L) (P0.05). CONCLUSIONS: The increased serum ASP level may be associated with a complemental mechanism against hyperlipidemia in children with PNS.