To provide a door entrapment detection device (10) and a door entrapment detection system that limit interference with a scheduled operation of a vehicle (1), a door entrapment detection device (10) includes a determination unit (42) and a reference value setting unit (43). The determination unit (42) (determination calculation unit) determines whether a door entrapment state is present based on a comparison result between an output value from a sensor (11) configured to detect rotation of a rotary body (12) provided at a leading end of a vehicle door (3) and a reference value (determination value) serving as a criterion for determining whether the door entrapment state is present. The reference value setting unit (43) (setting unit) changes the reference value determined by the determination unit (42) based on at least one of a surrounding state of the vehicle door (3) or an operation of the vehicle door (3).