A vehicle communication device including a processor, wherein the processor: receives first data, and second data that is different from the first data; generates third data based on the received first data and an encryption key; compares the second data and the third data, and authenticates the first data in a case in which the second data and the third data match; and as a result of comparisons that are carried out a plurality of times on receivings that are within a predetermined amount of time after start-up of a vehicle, determines that a case in which the second data and the third data do not match every time is a device abnormal state, and, as a result of the comparisons of the plurality of times, determines that a case that includes matching is a device operating state.