An offset calibration training method for adjusting a data receiver offset and a memory device therefor are provided. A method of performing a data receiver offset calibration includes storing a first parameter code, which is used to set a default data receiver offset calibration for the data receiver offset calibration, in a mode register, storing a second parameter code, which is used to set an optional data receiver offset calibration for the data receiver offset calibration, in the mode register, training the default data receiver offset calibration based on the first parameter code for the data receiver offset calibration, and training the optional data receiver offset calibration based on the second parameter code for the data receiver offset calibration.