Lubomirskiidae is a family of freshwater sponges from Lake Baikal in Russia.

[1] Lubomirskia baikalensis, Baikalospongia bacillifera and B. intermedia are unusually large for freshwater sponges and can reach 1 m (3.3 ft) or more.

[2][3] These three are also the most common sponges in Lake Baikal.

[2] Most sponges in the lake are typically green when alive because of symbiotic dinoflagellates (zoochlorella), but can also be brownish or yellowish.

[4] The family contains four genera and sixteen species:[5]