The embodiment of the invention provides a traffic signal lamp machine abnormity state processing method, a host and a slave computer; the host sends control information to the slave computer through a first communication channel, and sends verification information corresponding to the control information to the slave computer through a second communication channel; the host receives the first communication state information sent by the slave computer, wherein the first communication state information is determined by the slave computer through verifying the received control information and verification information; the host adjusts the communication channel used for sending the control information and verification information according to the first communication state information. Two communication channels are arranged between the host and the slave computer so as to respectively transmit the control information and the verification information, and can be adjusted in real time, thus timely finding communication abnormity, further switching the communication to the more reliable communication channel according to the abnormal conditions, ensuring the traffic signal lamp normal operation, and improving the traffic signal lamp stability.