A novel 3D metal-organic framework (MOF) [Pr₂(L)₃(H₂O)₅·H₂O]_n (Pr-1), (H₂L=4, 4′-oxybis(benzoic acid)) with a rare structure of broken layer net, was constructed under the condition of solvothermal synthesis. The structure and crystal net were analyzed and characterized. This rod net of Pr-1 is new to both RCSR and ToposPro databases, and is named as rn-12 as suggested. Due to the luminescent properties of H₂L and Pr(Ⅲ), the solid-state fluorescence property and sensing performance (solvents and metal ions) of Pr-1 were investigated. The sensing experiments indicated that Pr-1 could act as a fluorescence sensor to detect Cd²⁺ ions with good sensitivity. In addition, antibacterial activities show that Pr-1 exhibited stronger antibacterial activity against Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), and Bacillus subtilis (B. subtilis) compared to synthetic materials.