To explore the variation of crude fat in steamed or boiled peanuts, the peanut from market was steamed or boiled, then determined the amount of crude fat by Soxhlet extraction method according to GB/T14772-2008. The unprocessed sample was taken as control group. The effect of processing duration on the content of crude fat was studied. The results showed that steamed within 1.5 h the crude fat decreased 3.1 g/100g dry basis sample, remained the same after steamed over 1.5 h; the crude fat decreased 4.0 g/100 g dry basis sample when boiled for 3 h, remained the same after boiled over 1.5 h.