The blue-spotted salamander prefers marshes, flooded roadside ditches, and ponds in poorly drained woodlots and fields. The identification of this species and the Jefferson slamander is complicated by their ability to interbreed and the presence of two similar-looking hybrid species, the Tremblay's and silvery slamanders. These hybrid species are the result of blue-spotted and Jefferson salamanders interbreeding. The taxonomy of this species complex is still being studied by researchers in an attempt to clarify the status of these interbreeding salamanders. Blue-spotted salamanders move to breeding ponds at night, during or after rain in March and early April.
Males arrive at the pond before the females, who wait for more consistent weather before moving.
Both the blue-spotted and Jefferson salamanders have a prolonged courtship, in which the male clasps the female with his forelimbs while rubbing his chin from side to side over the female's head. Eggs are laid singly or in clusters of 10 to 40 eggs on the pond bottom or around submerged twigs. The aquatic larve are carnivorous, feeding on daphnia, aquatic insect larvae, tadpoles, and smaller salamander larvae. Transformation occurs in late August or early September. Adults spend the summer underground in tunnels beneath stumps and rocks, only emerging to feed in wet weather.