The γ radiation defects in shallow impurity implanted semi-insulating LEG GaAs have been studied by the deep level transient spectroscopy (DLTS) and the constant temperature capacitance transient technique. In Si-and Be-coimplanted semi-insulating LEC GaAs, there exists an electron trap Ｅ＇2 introduced by γ radiation, and both of the two original electron traps Ｅ01（０．２９８） and Ｅ02（０．３４１） are retnarkably enhanced by the radiation, by contrast, the original hole trap Ho3 is greatly reduced. There exist five electron traps,Ｅ＇01（０．２１６），Ｅ＇02（０．３４１），Ｅ＇2，Ｅ＇4 and Ｅ＇5（０．６０８）, which are caused by γ radiation in Si single-implanted semi-insulating LEC GaAs. The Ｅ01 and Ｅ＇01 are newly observed. by comparison with the GaAs grown epttaxially on a substract of GaAs with low resistivity, Si-and Be-coimplanted semi-insulating LEC GaAs possesses a smaller introduced rate of γ radiation defects, but the Si single-implanted semi-insulating LEC GaAs has a bigger one.