A one-size diaper that can be used from birth. The size can be adjusted according to the baby's body size, which is very economical and practical. Designed with a three?layer structure, it can be washed repeatedly without deformation, damage, or fading, and can prevent urine leakage. The outer layer is compounded with a TPU film with waterproof and breathable function, which has high elasticity and tensile resistance, can be stretched, and has good flexibility. The inner layer has the function of water permeability and anti?reverse osmosis, the fabric that touches the baby's skin has only a slightly wet feeling, which is different from general diapers without inner layer design. There is elastic closing soft waist and leg frames to prevent side leakage of urine. The size of the diaper can be adjusted according to the baby's body shapes.