〔Abstract〕 Objective To investigate the clinical and pathological features and risk factors of primary IgA nephropathy(IgAN) with foot process effacement(FPE). Methods The clinical and Oxford-type pathological data of 300 patients diagnosed with primary IgAN by renal biopsy were retrospectively analyzed, and the influential factors of IgAN foot process fusion were analyzed by multivariate logistic regression with significant clinical indicators. Results 300 cases of adult IgAN diagnosed by renal puncture biopsy were included, the extensive FPE group accounted for 15%. 156 cases(52%) were female and 144 cases(48%) were male. The median age of onset was 36(30,50) years. The median duration of renal biopsy was 8(1,24) months. The proportion of nephrotic syndrome in the extensive fusion group was higher(55.6%vs6.7%,P<0.05). There was no significant difference in the proportion of IgAN with hypertension among different degrees of FPE(P=0.092), but the systolic and diastolic blood pressure in the extensive FPE group were higher than those in the mild FPE group(P<0.05). The levels of total cholesterol(TC), triglyceride(TG), low-density lipoprotein cholesterol(LDL-c), and 24-hour urinary protein in the extensive FPE group were higher(P<0.05), but the levels of albumin, estimated glomerular filtration rate(eGFR) and hyperuricemia were low(P<0.05). There were no significant differences in hemoglobin, creatinine, and uric acid levels between the two groups(P>0.05). There was a higher proportion of endothelial cell proliferation(E1), segmental sclerosis or adhesion(S1), and cellular or cellular fibrous crescents(C1-2) in the extensive FPE group(P<0.05), while there was no significant difference in tubular atrophy or interstitial fibrosis(T1-2) between the two groups(P>0.05). Univariate logistic regression analysis showed that diastolic blood pressure, eGFR, TC, TG, and LDL-c were associated with extensive FPE in IgAN patients. Multivariate logistic regression analysis showed that elevated TC(OR=2.135,95%CI1.095-4.164,P=0.026) was an independent risk factor for extensive fusion of the foot process. Conclusion Compared with mild FPE, IgAN patients with extensive FPE had higher rates of blood pressure, blood lipid, nephrotic syndrome and hyperuricemia, slightly worse renal function, and more severe pathological manifestations of the Oxford-type. Elevated TC is an independent risk factor for extensive FPE in IgAN patients.