Congenital (hypo)dysfibrinogenemia patients may have obstetric complications during their pregnancies. In this study, we aimed to evaluate thromboelastography (TEG) as a potential tool for assessing the tendency of obstetric complications in those patients under non‐pregnant state. A total of 22 female subjects with congenital (hypo)dysfibrinogenemia were recruited. 9 subjects were with histories of obstetric complications and the other 13 subjects had at least one uneventful pregnancy without obstetric complications yet. The detailed clinical investigation and phenotype/genotype detection were carried out, and both kaolin activated TEG and functional fibrinogen TEG (FF‐TEG) were applied in all subjects. Significant difference were identified in all TEG parameters except for R and Angle between these two groups (p<0.05) by covariance analysis. Receiver operating characteristic (ROC) analysis of discrimination between these two groups of patients was performed for TEG parameters. Significantly high odds ratio (OR) of obstetric complications occurrence were demonstrated in K≥3.8 min, MA≤54.2 mm, CI≤‐3 (11.67, 95% CI 1.527‐89.121, p<0.05 in all), and MA‐CFF≤12.1 mm (20.00, 95% CI 1.967‐203.322, p=0.002). Moreover, MA‐CFF had better prognostic performance, with a corresponding area under ROC curve of 0.923 (range 0.815‐1.031, p=0.001). Our study suggests that (hypo)dysfibrinogenemia patients with values out of cut‐off values in TEG assays under non‐pregnant state may have a higher risk of obstetric complications occurrence when they are pregnant. This article is protected by copyright. All rights reserved.