The aim of this research is to develop a repetition multi- pass Nd:glass slab amplifier with output energy range of joules. A Nd: glass slab amplifier was developed with a high efficient repetition. Some analyze and experimental researchers, such as the gain, gain distribution, thermal effect, store energy and efficiency, etc. have been done. The maximum storage efficiency of the amplifier is up to 2.1 percent. A multi-pass amplification system by the Nd:glass slab amplifier was set up. Further analyze and experimental researches were carried out on some characters, such as the structure energy fluent distribution, amplification character, beam quality, ASE and self-Las character, etc. The experimental result shows that the amplifier produce the output energy of 1J with beam quality of six times diffraction limit.