Puppy love, also known as a crush, is an informal term for feelings of romantic love, often felt during childhood and early adolescence. It is an infatuation usually developed by someone's looks and attractiveness at first sight. Such feelings fade away when the object of attraction stays out of sight for a while, whereas the feeling of real love takes a long time to develop and does not fade with time and or in the absence of the other. It is named for its resemblance to the adoring, worshipful affection that may be felt by a puppy. Puppy love typically lasts between 2 months and 2 years, and is thought to be fueled by preadolescent hormones. Some scientists, however, think it is initiated as a result of the natural development of the brain at the onset of preadolescence.

The term can be used in a derogatory fashion, presuming the affair to be shallow and transient in comparison to other forms of love. Sigmund Freud, however, was far from underestimating the power of early love, recognizing the validity of "the proverbial durability of first loves".