Remote-focusing microscopy has recently attracted a lot of interest due to its high-speed axial scanning capabilities. In this paper, we modeled remote-focusing microscopy, based on a pair of long working distance objective lenses. Three-dimensional intensity distributions of the point spread functions (PSFs) are calculated, and no significant spherical aberrations are introduced over a large volume of 100 μm×100 μm×150 μm. The validity of the scheme is verified by imaging biological samples and microelectronic chips at the imaging depth of 150 μm without introducing aberrations in the experiment.