The present invention discloses an SAR imaging system matrix transposition device based on a SDRAM chip and a pattern interlacing method which are suitable for SAR imaging application with high timeliness requirements. According to the device features of an SDRAM chip, the SDRAM chip is fully utilized in an extra control command period generated by operations such as page jump, read/write, refreshand the like to allow the SAR imaging system matrix transposition device to achieve seamless joint when data is continuously input and output, and the transposition efficiency can reach 100%.