A state of charge estimation device for estimating a state of charge of an electric storage device includes a voltage measurement component, a current measurement component, and a controller component. The controller component is configured to, when estimation of state of charge of the electric storage device based on an accumulated amount of currents measured by the current measurement component is defined as a current accumulation method and the estimation based on an open circuit voltage (OCV) of the electric storage device measured by the voltage measurement component is defined as an OCV method, permit estimation of state of charge by the OCV method when a condition that an error in estimation of state of charge of the electric storage device by the current accumulation method exceeds an error in estimation of state of charge of the electric storage device by the OCV method is satisfied.