The phosphor Dy3+ doped M type gadolinium orthotantalate GdTaO4 was prepared successfully by traditional solid state reaction and the photoluminescence of GdTaO4: xDy3+ (0.01 ≤ x ≤ 0.10) has been investigated under ultraviolet and vacuum ultraviolet excitation. In the excitation spectra of GdTaO4: Dy3+, the overlap appears between the host lattice excitation, the excitation lines of Gd3+ and the f-f transitions of Dy3+, which indicates that the energy transfer could occur from the host to the Dy3+ ions. In the emission spectra of the samples, the intense emissions of Dy3+ have been expectably revealed both upon excitation at 365 nm and 147 nm. And the chromaticity coordinates of GdTaO4: xDy3+ have been correspondingly calculated. The results indicate that GdTaO4: Dy3+ would be a novel yellow emitting phosphor applied in light emitting diodes (LEDs), plasma display panels (PDPs) and mercury-free fluorescent tubes.