A modular mounting system for a night vision device includes one or more night vision monoculars, each night vision monocular having an imaging tube, a housing, and a first mounting shoe at a first position on the housing. A power supply has a first fastener thereon. A helmet mount at a first location on a helmet has a second fastener thereon. A power supply interface is located at a second location on the helmet and a second mounting shoe is provided on the power supply interface. The first mounting shoe is interchangeably and removably attachable to the first fastener and the second fastener, and, the first fastener interchangeably and removably attachable to the first mounting shoe and the second mounting shoe. In a further aspect, a firearm rail interface is provided to allow the night vision monocular to alternatively be positioned on a firearm accessory rail.