Ce3+ doped LiYF4 [Li(Y1-xCe x)F4] single crystals with various substitution level x were grown by micro-pulling down method and the optical properties and neutron responses were investigated. Transparent Li(Y1-xCex)F 4 single crystals with x= 0.001, 0.005, 0.01 could be grown without visible cracks and inclusions. The transmittances indicated over 70% above 310 nm and emission spectrum originated from 5d-4f transition on Ce3+ ion were observed at 309, 325 nm. The pulse-height of the crystals by aray irradiation indicated the crystal with x=0.001 was the largest light yjeld and the decay times systematically decreased with an increase of x which was shorter than Li-glass(GS20). Neutron responses revealed the light yjeld of the crystal with x =0.005 was quarter taht of Li-glass.