A hydrogen detection system can include an exposed detection element made of a catalytic metal which burns hydrogen so as to generate combustion heat. A hydrogen sensor can detect a hydrogen concentration based on a detected value of the detection element. A heating unit can heat the detection element. A hydrogen storage unit is included, and a hydrogen guiding pipe can guide the hydrogen from the hydrogen storage unit to the detection element. A flow rate adjusting device is attached to the hydrogen guiding pipe, and adjusts a flow rate of the hydrogen. A first dilution unit can dilute the hydrogen from the hydrogen storage unit with a dilution gas, and a controller can control the heating unit and the flow rate adjusting device.