CaY1-x-yAlO4∶xCe 3+, yTb 3+ phosphors are synthesized by the sol-gel method. The effects of single-doped Ce 3+ or Tb 3+ rare earth ions and their co-doping on the luminescence properties of the phosphors are discussed. The results show that the synthesized phosphors are pure samples with the tetragonal structure. The CaY1-xAlO4∶xCe 3+ phosphors emit blue light peaking at around 445 nm under an excitation wavelength of 368 nm. The CaY1-yAlO4∶yTb 3+ phosphors emit green light peaking at 418, 440, 491, 548, 589, and 625 nm under an excitation wavelength of 246 nm. In Ce 3+/Tb 3+ co-doped phosphors, the energy transfers from Ce 3+ to Tb 3+, which makes the luminescence of Tb 3+ enhanced. When the Ce 3+ and Tb 3+ co-doped phosphors are under an excitation wavelength of 368 nm or 378 nm, Tb 3+ emits a strong green light. The intensities of blue and green lights can be tuned by adjusting the doping concentrations of Ce 3+ and Tb 3+.