A fuel cell system, comprising: a fuel cell configured to be supplied with a fuel and a cathode gas, the fuel cell configured to generate an electric power with the fuel and the cathode gas; an evaporation portion configured to generate a water vapor from a reforming water supplied from a water tank; a reforming portion configured to generate the fuel with a source material for reforming supplied from a supply source (Gs) and the water vapor supplied from the evaporation portion, the reforming portion configured to supply the fuel to the fuel cell; a control device at least configured to control the fuel cell; at least one of a first flow sensor (11a2) configured to detect a flow amount of the source material for reforming and a second flow sensor (11c2) configured to detect a flow amount of the cathode gas; and at least one of switches (18b, 18c) configured to electrically connect/disconnect at least one of the first flow sensor (11a2) and the second flow sensor (11c2) to/from a power supply; wherein the control device includes an abnormality determination portion (15f, 15g) configured to determine whether at least one of an abnormality of a sensor and a communication abnormality occurs on a basis of the flow amount detected by the first flow sensor (11a2) and the second flow sensor (11c2), wherein the abnormality of the sensor serves as an abnormality of each of the first and second flow sensors (11a2, 11c2), the communication abnormality serves as a communication abnormality between the first flow sensor (11a2) and the control device, and between the second flow sensor (11c2) and the control device; and a reset process portion; and wherein each of the first flow sensor (11a2) and the second flow sensor (11c2) is configured to cause at least one of the abnormality of the sensor and the communication abnormality as a target flow sensor (11a2, 11c2), each of the switches (18b, 18c) is configured to electrically connect/disconnect the target flow sensor (11a2, 11c2) to/from the power supply as a target switch (18b, 18c), and the reset process portion is configured to operate a reset process reconnecting the target switch (18b, 18c) after disconnecting when the abnormality determination portion (15f, 15g) determines that at least one of the abnormality of the sensor and the communication abnormality occurs at the target flow sensor (11a2, 11c2), characterized in that the control device further includes a normal reset determination portion; and after the reset process portion operates the reset process, the normal reset determination portion is configured to determine whether the target flow sensor (11a2, 11c2), and the communication between the target flow sensor (11a2, 11c2) and the control device are normally reset based on the flow amount detected by the target flow sensor (11a2, 11c2). a fuel cell configured to be supplied with a fuel and a cathode gas, the fuel cell configured to generate an electric power with the fuel and the cathode gas; an evaporation portion configured to generate a water vapor from a reforming water supplied from a water tank; a reforming portion configured to generate the fuel with a source material for reforming supplied from a supply source (Gs) and the water vapor supplied from the evaporation portion, the reforming portion configured to supply the fuel to the fuel cell; a control device at least configured to control the fuel cell; at least one of a first flow sensor (11a2) configured to detect a flow amount of the source material for reforming and a second flow sensor (11c2) configured to detect a flow amount of the cathode gas; and at least one of switches (18b, 18c) configured to electrically connect/disconnect at least one of the first flow sensor (11a2) and the second flow sensor (11c2) to/from a power supply; wherein the control device includes an abnormality determination portion (15f, 15g) configured to determine whether at least one of an abnormality of a sensor and a communication abnormality occurs on a basis of the flow amount detected by the first flow sensor (11a2) and the second flow sensor (11c2), wherein the abnormality of the sensor serves as an abnormality of each of the first and second flow sensors (11a2, 11c2), the communication abnormality serves as a communication abnormality between the first flow sensor (11a2) and the control device, and between the second flow sensor (11c2) and the control device; and a reset process portion; and wherein each of the first flow sensor (11a2) and the second flow sensor (11c2) is configured to cause at least one of the abnormality of the sensor and the communication abnormality as a target flow sensor (11a2, 11c2), each of the switches (18b, 18c) is configured to electrically connect/disconnect the target flow sensor (11a2, 11c2) to/from the power supply as a target switch (18b, 18c), and the reset process portion is configured to operate a reset process reconnecting the target switch (18b, 18c) after disconnecting when the abnormality determination portion (15f, 15g) determines that at least one of the abnormality of the sensor and the communication abnormality occurs at the target flow sensor (11a2, 11c2), characterized in that the control device further includes a normal reset determination portion; and after the reset process portion operates the reset process, the normal reset determination portion is configured to determine whether the target flow sensor (11a2, 11c2), and the communication between the target flow sensor (11a2, 11c2) and the control device are normally reset based on the flow amount detected by the target flow sensor (11a2, 11c2).