The Anthocerotopsida (which means plant with flower-like horns) are non-flowering plants with spore-forming structures that may resemble small horns. It is a rare or very uncommon group, distributed worldwide, that tends to grow in soils with constant moisture or very humid periods.

The plant thallus consists of green lobes, ranging from a few millimeters to a few centimeters, attached to the substrate, translucent or not, appearing fragile and unable to stay moist without liquid water around them. The lobes may exhibit small structures such as propagules, central nerves, hairs, folds, or frequently nodules where symbiotic cyanobacteria live, which provide organic nitrogen to the plant. Their thallus lobes lack truly specialized cells, such as conducting vessels. The lower surface usually has elongated hair-like cells (rhizoids) that anchor the plant to the substrate. The cells of these thalli have only one copy of each chromosome, constituting the gametophyte phase in the life cycle of this group. On the upper surface of the lobes, but immersed in the thallus, the structures forming sperm and ovules appear. The sperm cells are released into the environment by breaking the epidermal layer and they swim in presence of water, aided by rain splashes, to the female organs containing an ovule. Fertilization of the ovule produces a cell with two copies of each chromosome (diploid cells) that will form the sporophyte phase. The sporophyte grows on the mother plant and is basically composed of a short stalk carrying a long cylindrical sporangium, with an epidermis containing stomata. The sporangium has a central support column and two lateral valves, which open upon drying to release the spores, although the sporangium continues to grow from bottom to top during spore release.

The class Anthocerotopsida includes the major part of species of the phylum Anthocerotophyta, and is related to the class Leiosporocerotopsida.