A new family of lanthanide metal–organic frameworks, LnL (Ln = Y, La–Yb, except Pm), were synthesized under hydrothermal conditions based on a semi-rigid trivalent carboxylic acid. All LnMOFs are isostructural based upon the analyses of single crystal and powder X-ray diffractions. The optical properties of compounds LnL can be easily tuned by doping methods, allowing for the syntheses of the materials with enhanced visible emission properties. Considering the intense blue-emission of the Dy compounds, it is expected that white light can be achieved by doping Dy and other red-emission lanthanide ions, such as Eu3+ or Sm3+. For the first time, without involving any emission from organic ligands, white-light emission was successfully realized by codoping Dy/Eu or Dy/Sm into analogic Gd compounds.