Laotong or LaoTong (in English: old sames; written: 老同 in Mandarin) is a type of relationship within Chinese culture, which was practised in Hunan, that bonded two girls together for eternity as kindred sisters.

There were two cultural practises in Hunan in past centuries that acknowledged women's social bonds. One was Laotong, the other was Laotang.

Chinese women commonly refer to each other as "Sisters." This is a recognition of the importance of women's supportive relationships, which helped them endure hardship over their lives. Preparation for marriage might involve a Laotang relationship between several young women; the sisterhood would be dissolved upon marriage. After marriage, new sisterhoods could be formed later between married or widowed women.

For Chinese women, the Laotong or "Old-Sames" relationship was the most precious friendship bond. This was a more rare and formal relationship between women. A woman could only have one Laotong, and the bond was for life.

Often a Laotong relationship would be formed when a marriage was contracted between families who were expecting babies. This was done before the babies were born. If both children turned out female against the hopes of their families, the daughters could be brought together as Laotong. An intermediary, in some places a matchmaker, would form a Laotong relationship between two girls, similar to an arranged marriage. The Chinese astrological profiles of the girls were considered during the matching process. It was unusual for a Laotong relationship to be broken.