The invention provides a method for handling data read out from a memory. In one embodiment, a controller corresponding to the memory comprises a ping-pong buffer. First, a first sector read time period required by the memory to read and output a data sector to the ping-pong buffer is calculated. A second sector read time period required by a host to read a data sector from the ping-pong buffer is calculated. A page switch time period required by the memory to switch a target read page is obtained. A total sector number is determined according to the first sector read time period, the second sector read time period, and the page switch time period. When the memory outputs data to the ping-pong buffer, a first buffer and a second buffer of the ping-pong buffer are switched to receive the data output by the memory according to the total sector number.