Abstract: The β -γ coincidence technique is a kind of important method to detect radio-active xenon isotopes for the Comprehensive Nuclear-Test-Ban Treaty (CTBT). The energy and resolution calibration of detectors is the first key technique. This paper describes in detail the energy and resolution calibration methods of NaI(Tl) and plastic scintillator detectors for the noble gas β-γ coincidence system SAUNAⅡ-Lab. NaI(Tl) detector’s energy and resolution for γ-ray were calibrated with γ radioactive point sources. Plastic scintillator detector’s energy and resolution for β-ray were calibrated by Compton scattering electrons of ¹³⁷Cs 661.66 keV γ-ray. And the results of β-ray energy resolution calibrated by Compton scattering electrons of ¹³⁷Cs were compared with the results of conversion electron of ¹³¹Xe^m. In conclusion, it is an easy and feasible method of calibrating plastic scintillator detector’s energy by Compton scattering electrons of ¹³⁷Cs, but detector’s resolution calibrated by Compton scattering electrons is higher than factual result.