It is adjacent to the community of Moosonee across the Moose River, from which it is accessible by water taxi in the summer, a 2-minute helicopter ride in the spring and fall during break and freeze up season and by either snowmobile taxi or by driving over the river by vehicle in the winter months.

It is flat and made up of marine clay, underlain by sedimentary rocks, mainly limestone, dolomite and shale.

Being situated close to James Bay, Moose Factory Island is affected by the Arctic tides which rise and fall twice daily, varying as much as 2.5 m (8 ft 2 in) from high to low tide.

[2] Moose Factory Island and the Moosonee area has a very cold humid continental climate (Köppen Dfb).

The climate data is from Moosonee, around 3 km (1.9 mi) to the west.