Background: In recent years

along with the development of the radioactive ion beam facilities

much progress has been achieved in studies of unstable nuclei. Main discoveries include exotic halo and cluster structures around the drip lines; shell evolution and new magic numbers in unstable nuclei; new effective interactions such as tensor force

three-body forces

new spin-orbit force; new modes of collective motion such as soft giant dipole resonance; multi-step process and strong couplings in nuclear reaction with unstable nuclei. Purpose: This review is focused mainly on the outline of the experimental methods which has been intensively applied to investigate the new aspects of unstable nuclei. Methods: Recently many new techniques have been used to the measurement of the basic properties of the ground state of unstable nuclei. Decay measurement

nuclear reaction at low and intermediate energies

fast beam and zero-degree spectroscopy are also widely used. The special development of these methods related to the study of unstable nuclei has been emphasized. Results and Conclusion: Plenty new phenomena of unstable nuclei were observed

which greatly expanded our studies on nuclear physics. With the development of facilities and experimental techniques

we may expect new experimental data coming soon

which would refine our knowledge of the nuclear physics. Abstract