A semiconductor device and a method of generating a power-on reset signal are provided. The semiconductor device includes a regulator configured to generate a regulated power supply voltage having a lower voltage value than a power supply voltage based on the power supply voltage and output the regulated power supply voltage to an internal power supply line, and a power-on reset circuit configured to generate a signal which has a first level at which reset is prompted immediately after power for the power supply voltage is turned on and which transitions to a second level at which reset release is prompted from the first level when a voltage value of the internal power supply line has risen as a power-on reset signal.