The angular dependence of the spin-flop transition in Gd₅Ge₄ has been examined by magnetization measurements of a single crystal. When the magnetic field vector is tilted away from the antiferromagnetic easy axis (c axis) toward the b axis, the spin-flop transition always remains first order in nature. However, when the field vector is tilted away from the c axis toward the a axis, the first order spin-flop transition is only observed over a narrow range of tilt angles (0<θ<20°), which serves as evidence that the Gd moments “flop” from the c axis to the a axis during the spin-flop transformation.