Genital morphology of Varanus mabitang is described for the first time, based on the hemiclitores of the holotype. The formerly invertedly fixed outer genital organs could be brought to subsequent eversion through a slight maceration and a partial reversion of the original fixation effects by storing the dissected and removed organs in 2% potassium hydroxide solution (KOH). Morphological features of the organs, especially the derived structures of the hemibaubella, corroborate the view that V. mabitang is presumably sister to another Philippine species, V. olivaceus, and this renders the subgenus Philippinosaurus polytypic.