A childhood sweetheart is a mutual term for a relationship (not a partnership) between young people. This can develop through a deepening friendship, physical attraction, or a natural connection.

The relationship is often non-romantic and lasts for a short to medium amount of time. This experience helps shape future relationships during childhood or adulthood. Usually, a person has only one childhood sweetheart, as this term represents an important step in growing up. The term applies to both people involved, which is why it is sometimes called "childhood sweethearts."

The relationship may include romantic feelings or remain a close friendship. Affectionate actions, such as kissing, hugging, holding hands, or cuddling, may occur. The term "first love" can also describe this type of relationship in some cases.

Sometimes, these friendships are restarted later in life after long separations or the loss of a partner. This can lead to marriage or another relationship in the future. Some examples of this have been shared in the media.