Dynamic key generation method and system

The invention provides a dynamic key generation method and system, and the method comprises the steps: randomly obtaining a time seed from a time pool, generating a first key, carrying out the encryption of private data through a symmetric encryption algorithm, wherein the encryption key is the first key, and carrying out the calculation of an obtained rootkey and an equipment factory number through an algorithm to generate a second key; encrypting the time seed by using a symmetric encryption algorithm, wherein the encryption key is a second key; the device generates a newest third secret key by combining the obtained rootkey of the device with the device factory number of the device end; calculating a fourth secret key through the third secret key; and decrypting the encrypted private data by using a symmetric encryption algorithm through the fourth key to restore effective data. The system is applied to the method. Based on a two-layer encryption security mechanism and a non-repeated key, a relatively safe