Echolalia is the unsolicited repetition of vocalizations made by another person (when repeated by the same person, it is called palilalia). In its profound form it is automatic and effortless. It is one of the echophenomena, closely related to echopraxia, the automatic repetition of movements made by another person; both are "subsets of imitative behavior" whereby sounds or actions are imitated "without explicit awareness". Echolalia may be an immediate reaction to a stimulus or may be delayed.

Echolalia occurs in many cases of autism spectrum disorder and Tourette syndrome. It may also occur in several other neurological conditions such as some forms of dementia or stroke-related aphasia.

The word "echolalia" is derived from the Greek ἠχώ (ēchō), meaning "echo" or "to repeat", and λαλιά (laliá) meaning "speech" or "talk" (of onomatopoeic origin, from the verb λαλέω (laléo), meaning "to talk").