Whether or not a 6-month-old baby needs a calcium supplement depends on the child’s specific condition, and if a calcium deficiency is diagnosed it needs to be supplemented. If your 6-month-old baby is in good nutritional condition and does not show symptoms of calcium deficiency such as restless sleep and waking up easily, he/she usually does not need to take additional calcium supplements. If your baby has frequent sleep disturbance, easy to wake up, etc., you should be alert to the occurrence of calcium deficiency or other diseases, you should bring your baby to the health center for examination in a timely manner, if diagnosed with calcium deficiency, you need to take calcium supplements under the guidance of a doctor. Six-month-old babies can supplement calcium by supplementing vitamin D, proper sun exposure and taking calcium supplements. Sun exposure can promote the body’s endogenous production of vitamin D. Vitamin D can promote calcium absorption, and children can take vitamin D supplements from birth to puberty. In the case of more serious calcium deficiency can be calcium supplementation, such as calcium gluconate. Parents should ensure that the baby’s diet is balanced and comprehensive, help the baby to develop a regular dietary habits, appropriate sun exposure, if necessary, follow the doctor’s advice to supplement vitamin D and calcium. All of the above drugs should be used under the guidance of a doctor to avoid the adverse consequences of calcium supplementation.