To provide a train wireless system in which a central device is cascade-connected to a plurality of wireless base station devices, and the wireless base station device 21 effectively performs notification to the central device.

The wireless base station device has an upper-approaching line and a lower-approaching line. An upper error detection means 32 detects an error of the upper-approaching line. If an error of the upper-approaching line is not detected by the upper error detection means 32, connection control means 31 and 15 control so as to connect to the central device through the upper-approaching line, but if an error of the upper-approaching line is detected by the upper error detection means 32, the connection control means control so as to connect to the central device through the lower-approaching line.