The erbium-trium aluminum garnet (Er:YAG) is a short-pulse laser that can be used for hard tissue ablation, soft tissue debridement and root canal decontamination. It can be effectively used in deciduous teeth removal, resin bonding, superordinate teeth extraction, lingual lacunae extension, root canal washing and other aspects. Because the operation is painless, it is more acceptable to children, hence it is very common in pediatric stomatology application research. This article reviews the application of Er:YAG in pediatric stomatology from the above aspects.