Polypodiidae may refer to:

• Polypodiidae (cnidarians), a zoological family that only includes Polypodium hydriforme, a cnidarian parasite of fish eggs
• Polypodiidae (plant), a botanical subclass of Equisetopsida sensu lato that includes the leptosporangiate ferns
• Polypodiidae a botanical subclass that only includes the fern family Osmundaceae

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