The oxidative degradation of toxic and non-biodegradable phenol by a high energy electron beam has been investigated. Ozone can effectively accelerate oxidation and degradation of phenol. The removal rate of phenol is reduced little even at depths much higher than eight times of effective penetration depth in the well-mixing conditions by aeration. Therefore, considerable decrease in a real absorbed energy for degradation of phenol was possible. Removal rate of phenol could also be improved by decreasing dose rate. Ring chemical compounds produced by phenol degradation can be easily removed upto nearly 90% by low adsorbed energy of 20 kGy but total organic compounds were difficult to reduce.