An association between circulating pentraxin-3 (PTX3) and the risk of preeclampsia (PE) remains to be established. We performed a meta-analysis of observational studies to evaluate their relationship.The PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure, and WanFang databases were searched for related observational studies evaluating PTX3 and PE risk. A random-effects or a fixed-effects model was used in the meta-analysis, depending on the heterogeneity among the included studies.Nine case-control studies were included, with 396 PE patients and 438 controls. The results showed that PTX3 was significantly higher in pregnant women with PE as compared to those without PE (standardized mean difference [SMD] = 2.48, P < .001), with significant heterogeneity (I2 = 98%), particularly for those over 30 years old (SMD = 3.75, P < .001). Subsequent analyses showed that patients with severe or early-onset PE had higher PTX3 levels compared to those with mild or late-onset PE (SMD = 0.93, P = .01), suggesting that PTX3 may be a marker of PE severity. The association between PTX3 and PE was not significantly affected by the statistical method used. Sensitivity analyses by omitting one study at a time did not significantly affect the results. However, the funnel plots were asymmetric, suggesting the potential existence of publication bias.PTX3 may be related to the risk and severity of PE in pregnant women. These results should be evaluated and confirmed in cohort studies.