To provide a practical vehicular information transmission device suitable for checking two or more staff members.

The device comprises a host device 18 that is connected to a communication network 16, a plurality of slave units that are disposed at each seat 14 of the vehicle 12 and carry out transmission of information with the host device 18, and a plurality of portable terminals 22 that are disposed for respective slave units 20, function as operating devices of the corresponding handsets 20 and obtain information from the communication network 16 through the host device 18. The host device 18 and the plurality of portable terminals 22 comprise a location detection means 32 that detects their respective locations corresponding to signals from a GPS satellite 30, and the host device 18 comprises a location confirming means 34 that confirms the location of each portable terminal 22 by asking each portable terminal 22 questions sequentially. This arrangement gives the portable terminal 22 carried by a staff member high availability and makes the carrier aware of its presence, resulting in reduced possibility of it being lost.