A data storage device and a data processing system having the same are disclosed. The data storage device includes a nonvolatile memory and a controller, coupled to the nonvolatile memory, configured to receive first and second commands generated by a host and control an operation of the nonvolatile memory in response to the first command. The controller includes a core configured to receive and process the first command, a trace circuit corresponding to the core and configured to generate and output first data, based on pieces of information generated while the core processes the first command, and a trace controller configured to control output of the first data and second data differing from the first data, based on a result of performing at least one authentication control operation corresponding to the second command.