We carried out transient optical absorption measurements of the conversion, induced by electron pulse irradiation, of the GaAs EL2 between the normal (EL20) and metastable (EL2*) states. It is found that no thermal barrier exists in the EL2* to EL20conversion when induced by electron pulse irradiation and that the yield of the EL20to EL2* conversion is much lower than that of the reverse conversion. These conversion processes were attributed to arise from the electron‐hole recombination at the EL2.