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A series of flume experiments with a silt loam taken from Beijing were conducted to measure water flow velocity with two methods, the electrolyte tracer method and dye tracer method. A solute injector, a data logger for control and data acquisition was used for flow velocity measurement. The experiment involved three slope gradients (5°, 10° and 20°), and three flow rates (64L/min, 128L/min and 256L/min). The results showed that the velocity of ephemeral gully water flow tended to decrease with slope length. The velocity increased with flow rate and slope gradient. The velocity measured by the electrolyte tracer method under the given experimental condition ranged from 0.55m/s to 1.60m/s, as compared with 0.71m/s to 1.45m/s by the dye tracer method. The velocities measured by the two methods were compared under different slope gradients and flow rates. The velocities measured by the dye tracer tended to be lower than those measured by the electrolyte tracer method. Considering the strong dilution and disturb effects of high rate water flow and strong turbulence on dye tracer, visual detection of dye movement should have caused later detection of the dye movement in water flow. All these indicate that the measured velocity of ephemeral flow seems rational.