The invention discloses a high-speed generation method of true random numbers. The high-speed generation method comprises the following steps of forming metastable ring oscillators with a plurality of metastable sub ring oscillators, allowing the metastable sub ring oscillators to work in a stable oscillation state or a metastable state alternately via a control signal, connecting a multiplexer with the metastable ring oscillators as entropy sources, generating a first random sequence and a second random sequence with the two independent entropy sources respectively, inputting the random sequences in an encryption operation unit, performing encryption operation by taking the first random sequence as plaintext data and the second random sequence as a key, and outputting ciphertext data as random number output. Compared with the prior art, a true random number generator is achieved in an encryption mode; isostatic correction is performed on the generated random number via an exclusive-or chain and a DES (data encryption standard) algorithm to achieve a combination of the random numbers generated by the two ring oscillators; and finally, a random number generation rate reaches 400 Mbit/s.