Chronic inflammation is associated with various malignant tumors. Bacterial lipopolysaccharides (LPSs) play a significant part in the event and development of prostate cancer. Dishevelled segment polarity protein 3 (DVL3) is a shared component of the Wnt/β-catenin and Notch signaling pathways, which are involved in tumor progression, chemoresistance, and maintenance of stem cell-like properties. According to reports, prostatic cancer cell invasion and proliferation are mediated by toll-like receptor 4 (TLR4). However, the role and regulation of DVL3 in prostate cancer and its relationship with TLR4 remain unclear. Survival curves were plotted to evaluate the relationship between DVL3 expression and prognosis in patients with prostate cancer. DVL3 was silenced in PC3 and DU145 cells using small interfering RNAs (siRNAs). Subsequently, cell counting kit-8 (CCK-8) assay, colony formation assay, transwell migration assay, and quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) were performed to investigate the role of DVL3 in cell proliferation and migration in vitro. The protein markers of potential pathways were analyzed via western blotting. DVL3 expression was linked to prognosis in patients with prostate cancer; In particular, patients with high DVL3 expression had a poor prognosis. LPS stimulation increased (p < 0.01) the expression of DVL3 in PC3 cells. DVL3 regulated tumor cell proliferation and migration by mediating the increase (p < 0.01) in TLR4 expression. Knockout of TLR4 validated that TLR4 played a crucial role in LPS-induced DVL3 expression. Silencing of DVL3 decreased (p < 0.01) the LPS-induced proliferation and migration of PC3 cells. Bacterial LPS-induced DVL3 promoted the multiplication and migration of prostate cancer cells through the TLR4 pathway. This study offers a valuable reference for the development and clinical application of targeted drugs for prostate cancer.