认知或认识（英语：cognition）在心理学中是指通过形成概念、知觉、判断或想象等心理活动来获取知识的过程，即个体思维进行信息处理（information processing）的心理功能。认知过程可以是自然的或人造的、有意识或无意识；因此，麻醉学、神经科学、心理学、哲学、系统学以及计算机科学在分析认知时，其分析的聚焦点以及脉络是不同的。

对认知进行研究的科学被称为认知科学。

Cognition is "the mental action or process of acquiring knowledge and understanding through thought, experience, and the senses." It encompasses processes such as knowledge, attention, memory and working memory, judgment and evaluation, reasoning and "computation", problem solving and decision making, comprehension and production of language, etc. Human cognition is conscious and unconscious, concrete or abstract, as well as intuitive (like knowledge of a language) and conceptual (like a model of a language). Cognitive processes use existing knowledge and generate new knowledge.