An injection control device has a current supply controller controlling a supply of an electric current for opening and closing a fuel injection valve, a current monitor monitoring the electric current supplied to the valve, and a boost controller performing a boost voltage generation control that generates a boost voltage from a power supply voltage by a tuning ON/OFF of a switching element for supplying a peak current to open the valve. When the current supply controller supplies the peak current to the fuel injection valve, the boost controller stops the boost voltage generation control in a stop period that includes a timing when an electric current supply amount takes a threshold value of the peak current.