Polyxenidae is a family of millipedes in the order Polyxenida. This family includes 109 species distributed among 23 genera. This family has a worldwide distribution, with species found on all continents except Antarctica.

Millipedes in this family range from 1.2 mm to 4.2 mm in length (not including the bundle of bristles at the tail end). All adults in this family feature 10 tergites in front of the telson and 13 pairs of legs. The male in this family features two to six pairs of pores on leg pairs 6 through 11. The male places his spermatophores on fine threads excreted from these pores.

The following subtaxa are recognised in the family Polyxenidae: