The disclosure relates to a data processing method and device and an encryption device. The method comprises the steps of: acquiring to-be-sent data of a client; according to a comparison result of a data length of the to-be-sent data and a size of a data block of a block encryption algorithm, encrypting the to-be-sent data by utilizing a preset secret key and adopting the block encryption algorithm or/and a stream encryption algorithm to obtain encrypted data; and sending the encrypted data to a gatekeeper, wherein the gatekeeper is in communication connection between the client and a server. By the data processing method and device and the encryption device which are disclosed by the disclosure, an encryption card and the safety isolation gatekeeper are utilized to carry out identity authentication and data encryption, and the server and the client can be compatible to various communication protocols in an existing production network without being changed, so that safety protection of the data is implemented.