The present patent application provides an oral nicotine-substituted cytisine atomized liquid and its preparation method. The oral nicotine-substituted cytisine atomized liquid includes the following components in mass percentage per 1 L of the oral atomized liquid: 0.1-10% of tobacco, 0.3-15% of cocoa extract, 0.1-0.9% of cytisine, 0.1-0.5% of TWEEN 80 and 75-90% of primer. The liquid can be obtained through the steps of weighing tobacco into an extraction tank, filtering the extract to obtain the filtrate, adding cocoa extract, cytisine and primer to the filtrate and mixing evenly.