Five-month-old babies always chewing their tongues are considered to be possibly related to the development of sense of taste and teething. Generally speaking, if there is no abnormality in the mouth and the development in all aspects is normal, the phenomenon of chewing the tongue is considered normal. The baby grows up slowly, the development of the nervous system is gradually perfected, the tongue and the muscles of the mouth are flexible, and the phenomenon of chewing the tongue occurs. The baby’s sense of taste is also developing, and using the tongue to explore the surrounding environment, and chewing the tongue is also a kind of performance. There is also the possibility that the baby is going to grow teeth, and before teething, the gums may feel itchy, and the baby may massage the gums with the tongue, resulting in the phenomenon of chewing the tongue. It is recommended that you take your child to the hospital for an oral examination to rule out oral diseases.