A code checking method includes: causing a compiler to generate a map file and a low-level code file(s) according to a high-level code file(s); obtaining target function information from the map file; finding a target code file from the low-level code file(s); obtaining a first return command of a target function name of the target function information from the target code file; traversing the low-level code file(s) to obtain each calling module name and a second return command of each calling function name; obtaining a second storage area of each calling module name from the map file; and generating a check failure result when calling of a target function name by each calling function name is not complied with a bank-switching compile form according to a first storage area of the target function information, the first return command, each second storage area, and each second return command.