A signal detection method and a signal detection device are provided. The signal detection method includes steps of: performing channel estimation based on a signal received by each of antennae, to acquire a channel estimation matrix for transmitters multiplexing on identical time-frequency resources on each of the antennae; determining an equivalent Pattern Division Multiple Access (PDMA) channel estimation matrix for each of the antennae based on a PDMA encoding matrix, and acquiring an equivalent multi-antenna PDMA channel estimation matrix for all the antennae based on the equivalent PDMA channel estimation matrix for each of the antennae; performing a joint detection based on the equivalent multi-antenna PDMA channel estimation matrix, an equivalent multi-antenna received signal vector and a set of constellation points of the transmitters multiplexing on the identical time-frequency resources, to acquire Log Likelihood Ratios (LLRs) for the transmitters; and decoding the LLRs for the transmitters, to acquire multi-user information at transmitting end.