延宕（英语：Procrastination），俗称“拖延症”，是一种个性行为，即将要做的事或者任务推迟到稍后时间的行为。延宕者通常会对开始或完成任何任务或决定感到焦虑，而将延宕作为应付焦虑的一种机制。

心理学研究者有三个标准来界定延宕：

对个人来说，轻微程度的延宕是正常的，当其开始阻碍你的正常工作，就需要认真对待它了。慢性或长期的延宕行为，暗示着潜在的心理及生理紊乱。

拖延的英语：Procrastination来源于拉丁语：Procrastinatus："pro-"（向将来，向前）加上"crastinus"（明天的）。这个词最早出现于爱德华·霍尔出版于1548年的一部作品。

Procrastination is the avoidance of doing a task which needs to be accomplished. It is the practice of doing more pleasurable things in place of less pleasurable ones, or carrying out less urgent tasks instead of more urgent ones, thus putting off impending tasks to a later time. Sometimes, procrastination takes place until the "last minute" before a deadline. Procrastination can take hold on any aspect of life — putting off cleaning the stove, repairing a leaky roof, seeing a doctor or dentist, submitting a job report or academic assignment or broaching a stressful issue with a partner. Procrastination can lead to feelings of guilt, inadequacy, depression and self-doubt.