A natural rubber composition includes a natural rubber, a carbon black filler in an amount of 40 phr based on an amount of the natural rubber, a sulfur crosslinking agent in an amount of 1 phr of based on the amount of the natural rubber, and an accelerator to adjust vulcanization physical properties and a dynamic ratio. The accelerator includes a semi-ultra accelerator in an amount of 0.3 to 1 phr based on the amount of the natural rubber, a delayed accelerator in an amount of 1 to 2 phr based on the amount of the natural rubber, and an ultra accelerator in an amount of 0.3 to 1 phr based on the amount of the natural rubber.