The boy and his parents were visiting a residence yesterday in an isolated area in southern Virginia on Monday when he found the firearm on a dresser, local NBC affiliate WWBT reported.
The toddler was alone in a bedroom, picked up the firearm and pulled the trigger, shooting himself in the head, WWBT said.
The two-year-old was rushed to a hospital in the state capital of Richmond, where he died of his injuries yesterday.
Gun-control advocacy group Moms Demand Action For Gun Sense in America said that on average, around 100 children under the age of 17 die each year in the United States in firearm accidents.