Objective To explore the correlations of levels of blood lipids with clinicopathological characteristics and levels of complement components C3 and C4 in patients with immunoglobulin A nephropathy (IgAN).Methods One hundred and nineteen patients with IgAN diagnosed by renal biopsy in the Department of Nephrology of the First and Second Affiliated Hospital of Bengbu Medical College from January 2018 to December 2021 were selected. They were divided into abnormal group [levels of triacylglycerol (TG) ≥ 2.26 mmol/L and/or total cholesterol (TC) ≥ 6.22 mmol/L and/or high-density lipoprotein (HDL) < 1.04 mmol/L, n = 84] and normal group (n = 35) according to the levels of blood lipids. The clinicopathological characteristics of the two groups were compared. The Pearson method was applied to analyze the correlations between levels of blood lipids (TG, TC, and HDL) and levels of C3 and C4.Results There was no statistically significant difference in age, sex composition, systolic blood pressure, diastolic blood pressure, levels of hemoglobin, albumin and blood creatinine, eGFR, levels of blood urea nitrogen, blood uric acid and 24-hour urine protein, urine red blood cell count, CKD stage, glomerulosclerosis, area of renal tubular atrophy, glomerular crescent formation, degree of interstitial blood vessel injury, inflammatory cell infiltration, or histological grade assessed via Lee's grading system between the abnormal group and the normal group (P > 0.05). The BMI and levels of C3 and C4 in the abnormal group were higher than those in the normal group (P < 0.05). The serum level of TG was positively correlated with the level of C4 (r = 0.247, P < 0.05), but was not correlated with the level of C3 (r = 0.102, P > 0.05). The serum level of TC was positively correlated with the level of C4 (r = 0.240, P < 0.05), but was not correlated with the level of C3 (r = 0.029, P > 0.05). There was no correlation between the serum level of HDL and levels of C3 and C4 (r = 0.080 and 0.171, P > 0.05).Conclusions Some patients with IgA nephropathy exhibit abnormal levels of blood lipids, and serum levels of TG and TC are positively correlated with the level of C4 in these individuals.