Microwave-induced oligomerization of methane has been extensively investigated for many years. Very important factors that control the oligomerization of methane were studied, including factors such as microwave frequency, time the materials are in the reaction zone, and nature of the catalysts. Activated carbon, iron, and nickel were tested for the activation of methane. Experiments were conducted at fixed frequencies of 2.4 and 4.6 GHz and at variable frequency over the range of 2-7 GHz with a sweep rate of 0.5 s. The power used for all experiments was 500 W. Changes in product distribution, because of changes in frequency, have been observed, most probably because of the different transient heating patterns that occur at different values of frequency. Oligomers ranging from C-2s to C-8s Compounds were obtained, in which C-2s compounds were the most abundant. Benzene was produced, with a selectivity of 28%.