Pentraxin 3 (PTX3), a member of the c-reactive protein family, is a long pentraxin protein and a pro-inflammatory marker. However, the role of PTX3 in preeclampsia (Pe) remains to be elucidated. Thus, the present study aimed to investigate the biological role and mechanisms underlying PTX3 in Pe. in the present study, PTX3 was overexpressed in trophoblasts and the subsequent changes in cell proliferation, cycle distribution and invasion were observed using cell Counting Kit-8, flow cytometry and Transwell assays, respectively. Moreover, the expression levels of MMP2 and MMP9, proteins associated with the development of Pe, were detected using reverse transcription-quantitative Pcr and western blot analysis. Following treatment with interleukin (il)-1β, the expression levels of PTX3 were measured. Furthermore, subsequent changes in cell proliferation, cycle distribution and invasion were investigated following overexpression of PTX3 and treatment with il-1 receptor antagonist (il-1ra). overexpression of PTX3 inhibited the proliferation, cycle and invasion of HTr-8/SV neo and JeG3 cells. Moreover, treatment with il-1β increased the expression of PTX3 in HTr-8/SV neo and JeG3 cells, which was suppressed following treatment with the il-1β antagonist. Following PTX3 overexpression and treatment with il-1ra, the inhibitory effects of PTX3 overexpression alone on the invasion of HTr-8/SV neo and JeG3 cells were attenuated. in conclusion, these results indicated that il-1β could induce PTX3 upregulation, which led to the inhibition of the proliferation, invasion and cell cycle of trophoblasts, thereby promoting the progression of Pe.