A command processing method and a storage controller are provided. The command processing method includes performing a command merging process on commands sequentially received by a command queue. The command merging process includes an initialization step and multiple iterations. The initialization step includes transmitting the commands from the command queue to a continuity checking pool (CCP), transmitting an initial command of the commands from the CCP to a continuity list (CL) and setting a range of the CL. Each of the iterations includes transmitting the commands from the command queue to the CCP; determining whether the commands in the CCP and the range of the CL conform to a continuity condition; and when the commands in the CCP and the range conform to the continuity condition, appending the first command to the CL and resetting the range of the CL according to the first command.