A vehicle to vehicle communication device including a satellite vehicle signal reception means for suppressing a decrease in relative position accuracy with a small communication amount during a unit time, a communication means, a kinematic acquisition means, a positioning means, a first vehicle information storage means, a second vehicle information storage means configured to record satellite vehicle information and the velocity vector of the second vehicle in each time, a relative position calculation means configured to calculate a relative position from the velocity vector of the first vehicle, the velocity vector of the second vehicle, and the satellite vehicle information, a requested satellite vehicle number generation means configured to generate a requested satellite vehicle number notifying the second vehicle of a satellite vehicle number observed by the first vehicle, and a transmitting satellite vehicle information generation means configured to generate information to be sequentially transmitted to the second vehicle.