The invention relates to the field of electronic 
payment terminals and discloses a method and device for safely collecting and distributing transmission keys. The method includes the generation step and the distribution step. The generation step mainly includes the sub-steps that an operator card is authenticated, a complete 
machine serial number and a working 
certificate are loaded, and activation operation is performed on a POS terminal. The distribution step mainly includes the subs-steps that 
encryption equipment performs 
encryption and signature on SN-TK data packets in an MTMS 
system again, and then the SN-TK data packets are distributed to a KMS 
system. The method and device have the advantages that when each POS terminal is produced, a transmission key (TK) is generated at random, and it is guaranteed that TK data collected by each POS terminal have uniqueness; in the process of TK collection, strict permission 
verification is performed on an operator, so that safety is guaranteed; in the process of distribution, strict valid 
verification, and secondary switching 
encryption and signature are performed, so that accuracy of the collected TK data is guaranteed in the production process.