This study aims to provide new knowledge regarding the effect of MnO₂ co-presence on efficiency of Cr(VI) removal with Fe(0). Non-disturbed batch experiments (≤40 days) were conducted using two types of Fe(0) (milli- and micro-sized), two Cr(VI) concentrations (5 and 100 mg/L), in three different systems (“Fe(0) only”, “MnO₂ only”, and “Fe(0) + MnO₂”), at an initial pH value of 6.9. Compared to “Fe(0) only” system, the efficiency and rate of Cr(VI) removal were highly promoted in “Fe(0) + MnO₂” system; moreover, while for the “Fe(0) only” system removal of Cr(VI) was severely hindered by increasing Cr(VI) concentration, in “Fe(0) + MnO₂” system comparable high efficacies were noticed both at low and high concentration. Recycling experiments indicated that total Cr(VI) removal capacity of “Fe(0) + MnO₂” system was up to 48.1 times greater than of the “Fe(0) only” system. Enhanced removal of Cr(VI) with Fe(0) was achieved at low doses of MnO₂, with an optimal mass ratio Fe(0):MnO₂ of 4:1. The favorable synergistic effect observed in “Fe(0) + MnO₂” system was ascribed to capacity of MnO₂ to accelerate Fe(0) oxidative dissolution, and to generate supplementary amounts of secondary adsorbents/reductants with removal ability towards Cr(VI). This study provides compelling evidence that “Fe(0) + MnO₂” system could represent a highly efficient and cost-effective alternative for the abatement of Cr(VI) aqueous pollution.