By employing diethyl 1,3-propylidenebis(4-oxybenzoate) as a precursor, the new three-dimensional metal-organic framework [La2L2(HL)2]n [L = 1,3-propylidenebis(4-oxybenzoate)] was prepared and characterized by single-crystal X-ray diffraction analysis, elemental analysis, infrared spectroscopy, and thermogravimetric analysis. The compound crystallizes in the triclinic space group P, with cell parameters: a = 8.299 (2) Å, b = 14.127 (3) Å, c = 14.520 (3) Å, α = 112.43 (3) °, β = 103.10 (3) °, γ = 95.28 (3)°, V = 1502.2 (5) Å3, and Z = 1. Under hydrothermal reaction conditions, two ester groups of the ligand hydrolyzed into carboxylate groups. The carboxylate groups coordinated in situ to metal ions to form the 3D coordination polymer. It exhibits a 10.4 × 10.6 Å rhombic channel along the  direction. On the basis of the results of TG analysis, the structure is thermally stable up to ≈ 400 °C.