A method for performing read acceleration, an associated data storage device and controller thereof are provided, where the method is applicable to the data storage device and the controller. The method includes: receiving a write command from a host device, and performing programming on a non-volatile (NV) memory element within a plurality of NV memory elements according to the write command; recording operation command-related information corresponding to the write command; when a read command having high priority exists in a queue corresponding to the NV memory element, suspending performing programming on the NV memory element; executing the read command; and after executing the read command, continuing performing programming on the NV memory element at least according to the operation command-related information.