A new orthorhombic phase of Na2LaOPO4 (sodium lanthanum oxyphosphate), and novel Na2NdOPO4 (sodium neodymium oxyphosphate), Na2SmOPO4 (sodium samarium oxyphosphate) were synthesized by solid state reactions of Na2CO3, NH4H2PO4, and Ln(2)O(3) (Ln = La, Nd, and Sm). The unit cell dimensions were calculated using their X-ray powder diffraction data, which were a 13.60(1), b = 12.71(1), and c = 6.96(1) angstrom, a = 13.466(5), b 12.547(6), and c = 6.932(5) angstrom, and a = 13.54(1), b = 12.577(8), and c = 7.047(5) angstrom, respectively, and the probable space group was Pmm2. Using the same procedure orthorhombic Na2DyOPO4 (sodium dysprosium oxyphosphate), Na2HoOPO4 (sodium holmium oxyphosphate), Na2ErOPO4 (sodium erbium oxyphosphate), and Na2YbOPO4 (sodium ytterbium oxyphosphate) were also prepared for the first time in this work. The IR data of the compounds agreed with the values given in the literature. The Raman data and SEM micrographs of the synthesized compounds are given for the first time in this report.