Based on the modified coupled-wave equations of Kogelnik, the dynamical diffraction properties, energy oscillation and pulse splitting of a sinusoidal volume holographic grating (VHG) illuminated by a femtoscond pulse with respect to the grating parameters and readout pulse parameters are studied. Result shows that the refractive index modulation of VHG and central wavelength of the readout pulse will affect the energy oscillation period, while the grating period has no effect on the energy oscillation period, but it will affect the angle between the line connected by centers of diffracted wave packets and the time axis. Based on group velocity and group delay, explanations on these phenomena are given. In the latter stage, diffracted pulse splits into two pulses, the pulse interval between them depends on the thickness and refractive index modulation of the VHG, and independent of the grating period, we explain it with the localization property of light field propagation.