The present disclosure describes an apparatus and method for estimating state of health (SOH) of a battery. The apparatus for estimating state of health of a battery includes a sensing unit for measuring a battery voltage and current within a predetermined charging voltage range; a memory unit storing the battery voltage and current values measured by the sensing unit and SOH-based ampere counting values, obtained by an ampere counting experiment of a battery whose actual degradation degree is known; and a control unit for calculating an ampere counting value by counting the measured current values stored in the memory unit within the charging voltage range, and estimating a SOH value by mapping the SOH value corresponding to the calculated ampere counting value from the SOH-based ampere counting values stored in the memory unit.