The American marten (Martes americana) is a small, slender-bodied, carnivorous mammal found throughout the northern portion of North America. Our study focused on the populations in the Manistee National Forest in Michigan’s Lower Peninsula and the Hiawatha National Forest in Michigan’s Upper Peninsula. Food availability is a large limiting factor to American marten populations due to their high metabolism and low fat storage. This can be especially important for lactating females that may have up to five kits to sustain. Kit-rearing female martens were fitted with radio collars and radio telemetry was used to track them to den sites. Scat, prey remains and remotely-triggered cameras were used to identify diet components. We sought to obtain an understanding of reproducing female marten diets in order to maintain optimal marten habitat. We observed martens behaving as generalists, consuming many types of prey. Small prey were consumed more often, but large prey provided the majority of their caloric intake. Gray squirrels were especially important prey for lactating females. We documented consumption of eastern moles and the delivery of multiple prey to the den at the same time, both previously unreported for this species. This is novel research that can be used by the Little River Band of Ottawa Indians, the Sault Sainte Marie Tribe of Chippewa Indians, the United States Forest Service and the Michigan Department of Natural Resources to manage for marten habitat in Michigan.