Apocrita is a suborder of insects in the order Hymenoptera.

Apocrita includes wasps, bees and ants, and consists of many families. It includes the most advanced hymenopterans and is distinguished from Symphyta by the narrow "waist" (petiole) formed between the first two segments of the actual abdomen; the first abdominal segment is fused to the thorax, and is called the propodeum. Therefore, it is general practice, when discussing the body of an apocritan in a technical sense, to refer to the mesosoma and metasoma (or "gaster") rather than the "thorax" and "abdomen", respectively. The ovipositor of the female either extends freely or is retracted, and may be developed into a sting for both defense and paralyzing prey. Larvae are legless and blind, and either feed inside a host (plant or animal) or in a nest cell provisioned by their mother.

Apocrita has historically been split into two groups, "Parasitica" and Aculeata, but these are rankless groupings in present classifications, if they appear at all. Parasitica is an artificial (paraphyletic) group comprising the majority of hymenopteran insects, with respective members living as parasitoids on what amounts to nearly "every other species of insect", and many non-insects. Most species are small, with the ovipositor adapted for piercing. In some hosts the parasitoids induce metamorphosis prematurely, and in others it is prolonged. There are even species that are hyperparasites (that which are parasitoids on other parasitoids). The Parasitica lay their eggs inside or on another insect (egg, larva or pupa) and their larvae grow and develop within or on that host. The host is nearly always killed. Many parasitic hymenopterans are used as biological control control agents to control pests, such as caterpillars, true bugs and hoppers, flies, and weevils.