A train information management device that is equipped on each car of a train, that monitors on-board devices, and that collects car information to control and manage operation of the train, and that selects a brake notch to be output to a brake control device from among a plurality of brake notches output from a plurality of brake-notch creating devices each of which includes a first and a second processing units that are independent of each other, the train information management device comprising: a first comparison processing unit to which brake notches created by the first and the second processing units in each of the brake-notch creating devices are input, that performs comparison processing on all of the input brake notches based on software processing, and that determines and outputs a brake notch producing a largest brake force; characterised by, a second comparison processing unit to which brake notches created by the first and the second processing units in each of the brake-notch creating devices are input, that performs comparison processing on all of the input brake notches based on software processing independently of the first comparison processing unit, and that determines a brake notch producing a largest brake force; the second comparison processing unit determines whether an output from the first comparison processing unit is available, and outputs the determined brake notch to the brake control device only when an output from the first comparison processing unit is not available, and a selection switching unit that performs such processing of selecting the brake notch output from the first comparison processing unit by a switching control of the second comparison processing unit to output to the brake control device when an output from the first comparison processing unit is available, and of selecting the brake notch from the second comparison processing unit by a switching control of the second comparison processing unit to output to the brake control device when no output from the first comparison processing unit is available, based on software processing, wherein the second comparison processing unit monitors an output from the selection switching unit to the brake control device, and only when there is no output thereto, outputs a control signal to an emergency braking unit to output an emergency brake command from the emergency braking unit to the brake control device. a first comparison processing unit to which brake notches created by the first and the second processing units in each of the brake-notch creating devices are input, that performs comparison processing on all of the input brake notches based on software processing, and that determines and outputs a brake notch producing a largest brake force; characterised by, a second comparison processing unit to which brake notches created by the first and the second processing units in each of the brake-notch creating devices are input, that performs comparison processing on all of the input brake notches based on software processing independently of the first comparison processing unit, and that determines a brake notch producing a largest brake force; the second comparison processing unit determines whether an output from the first comparison processing unit is available, and outputs the determined brake notch to the brake control device only when an output from the first comparison processing unit is not available, and a selection switching unit that performs such processing of selecting the brake notch output from the first comparison processing unit by a switching control of the second comparison processing unit to output to the brake control device when an output from the first comparison processing unit is available, and of selecting the brake notch from the second comparison processing unit by a switching control of the second comparison processing unit to output to the brake control device when no output from the first comparison processing unit is available, based on software processing, wherein the second comparison processing unit monitors an output from the selection switching unit to the brake control device, and only when there is no output thereto, outputs a control signal to an emergency braking unit to output an emergency brake command from the emergency braking unit to the brake control device.