Tetragonal scheelite-like single crystals NaEr(WO 4) 2 (NEW) have been grwon by using RF-heating Czochralski (CZ) method for the first time.Its transmittance spectrum was measured,comparing with that of NaY(WO 4) (NYW) crystal,its cut-off wavelength at UV-band is longer than NYW.It is caused by the bigger polarizing ability of Er 3+ than Y 3+.The infrared transmittance and Raman spectra were also measured,the factor group analysis was made and the lattice vibration frequency was assigned.