A white light on-axis digital holographic microscopy based on spectral phase shifting is described. We show experimentally that the spectral phase shifting based on-axis digital holographic microscopy can be used as an alternative to the PZT based phase shifting digital holographic microscopy. The proposed spectral phase shifting approach can provide a speckle-free capability since it employs the partial coherent source produced by combining a white light source and a spectral tunable filter. Another benefit of the proposed white light on-axis digital holographic microscopic system stemmed from spectral phase shifting approach is in the capability of providing a full color 3-D spectral section imaging.