The invention relates to a traditional Chinese medicine for treating primary lung cancer, which is characterized by comprising the following Chinese herbs as main components: 30g of radix astragali, 12g of raw rhizoma atractylodis macrocephalae, 30g of root of straight ladybell, 12g of asparagus, 30g of selaginella doederlleini, 30g of salvia chinensis, 30g of herba oldenlandiae, 15g of honeysuckle, 15g of subprostrate sophora, 15g of selfheal, 15g of varech, 12g of oarweed, 30g of arisaema cum bile, 15g of trichosanthes bark, 30g of raw oyster, and the like. A preparation method of the traditional Chinese medicine comprises the following steps: putting the Chinese herbs into a container, dipping the Chinese herbs into water, frying the Chinese herbs with slow fire for 20min, and taking out 200ml of decoction. One dose of the decoction is taken after breakfast and dinner every day, and ten dosages are taken as one period of treatment. The prescription is prepared from pure Chinese herbs by a traditional preparation method, reserves the medical property, has the efficacy of nourishing Yin and moisturizing the lung, clearing away heat and toxic material, flexibly and rigidly resolving phlegm and enhancing the immunizing power, achieves the aim of treatment and has no side effect.