Rare-earths (Pr, Ho) doped double tungstates NaY(WO4)2 crystals were prepared by using Czochralski (CZ) pulling method. Their absorption spectra have been measured in the region 300-2000nm at room temperature. A band gap of eigentransition of 3.92eV was obtained. The three phenomenological parameters were calculated through fitting of the calculated and measured oscillator strengths. J-O theory was used to evaluate the spontaneous emission probabilities, stimulated emission cross sections, branch ratios and energy level lifetimes of some useful transitions of Ho3+ ions in NaY(WO4)2 crystals. The obtained three phenomenological J-O intensity parameters Ω1 are Ω2=2.17×10-19, Ω4=1.58×10-19, Ω6=3.24×10-20 for pr3+; Ω2=1.64×10-19, Ω4=7.43×10-20, Ω6= 1.60×10-20for Ho3+.