The authors evaluated plasma pentraxin 3 (PTX 3) levels in preeclamptic patients and determined the relationship between albuminuria and plasma PTX 3 levels. During a period of one year, 29 patients with severe or mild preeclampsia and 49 healthy pregnant women were included in the cross-sectional study. The two groups were compared each other with PTX 3 levels. The relationship between PTX 3 levels and urea, creatinine, AST, ALT, CRP, LDH, platelet count, and spot urine protein/creatinine rate were evaluated. PTX 3 level was significantly high in the preeclamptic group (p < 0.05). No significant correlation was found between serum PTX 3 level and urea, creatinine, AST, ALT, CRP, LDH, platelet, and spot urine protein/creatinine rate (p > 0.05). PTX 3 is a biochemical parameter that shows endothelial dysfunction. The authors believe that PTX 3 can be a valuable parameter to predict preeclampsia according to the significantly high PTX 3 levels in preeclamptic patients.