Sennertia is a genus of mites in the Chaetodactylidae family.

Some of these mites are parasites or commensals of bees, but the presence in some bees of specialized structures for carrying mites (acarinarium) indicates the mutualistic nature of the relationship of some species (Sennertia sayutara, Sennertia devincta).

[1] Most species of the genus Sennertia settle on adult bees as heteromorphic deutonymphs, but the species Sennertia vaga has no deutonymph and settle on adult bees in the eating adult stages.

Most species occur on small carpenter bees (Ceratina) and large carpenter bees (Xylocopa) of the family Apidae.

A few species (Sennertia vaga-group) are associated with Centris (Paracentris) in the Neotropics.