Both theoretical and experimental researches on light-emitting diode (LED)-based digital holography are carried out.The propagation of the mutual intensity of the system is investigated under the premise that the LED is spatially incoherent and temporally quasi-coherent.A simple formula describing holographic fringe formation process with partially coherent illumination is found.The formula shows that the hologram fringe formation process can be presented as a linear space-invariant filtering operation.The filtering operation suppresses speckle noises and is also expected to experience a loss of resolution.The bandwidth of the filter is determined by the bandwidth of the secondary light source as well as diffraction distances of the object.Some methods are proposed to improve the resolution according to the theoretical analysis.Corresponding experiments are conducted and the results demonstrate the validity of the theoretical analysis.