In a recent Letter by Seo et al. [Opt. Lett.37, 4976 (2012)], the numerical correction of the quadratic phase distortion introduced by the microscope objective in digital holographic microscopy (DHM) has been presented. In this comment, we would like to draw to the attention of the authors and the readers in general that this approach could not be the optimal solution for maintaining the accuracy of the quantitative phase via DHM. We recall that the use of telecentric imaging systems in DHM simplifies the numerical processing of the phase images and produces more accurate measurements.