The disclosure provides state-of-charge (SOC) and state-of-health (SOH) estimation methods of a battery pack. The SOC estimation method of the battery pack includes the following steps. First, a current resting time, a current battery temperature, and a current measured open circuit voltage corresponding to a current initial power-on time of the battery pack are obtained. Next, an SOC value corresponding to the current initial power-on time is determined according to the obtained current resting time, current battery temperature, current measured open circuit voltage, and a relational expression between an open circuit voltage, a resting time, a battery temperature, and an SOC value at predetermined different battery temperatures, so that the battery pack can be characterized according to the obtained SOC value.