Diplaziopsidaceae is a family of ferns in the order Polypodiales, class Polypodiopsida. They are described as medium-to-large ferns, which grow near streams in forested areas. Their rhizomes are thick and decumbent to erect. Maarten J. M. Christenhusz and Xuan-Chun Zhang originally described the family in 2011 by including the three genera Diplaziopsis C.Chr, Hemidictyum C.Presl, and Homalosorus Small ex Pic.Serm. But later that year Samuli Lehtonen showed Hemidictyum to be a sister to Aspleniaceae, so they determined that Hemidictyum should be placed in its own family, Hemidictyaceae.