The invention relates to a pollination method for a purity-conservation Chinese cabbage breeding material. The method comprises the steps of: conducting soil preparation, harrowing, ridging, levelling, treading and top ridging; selecting a Chinese cabbage plant, removing old, diseased and rotten leaves, cutting away the upper half of the plant capitulum, dipping the root of the whole plant in a mixed solution of 100 times of carbendazim and chlorothalonil, then carrying out field planting to the plant in the middle of the ridge back, treading the root, and coating the root with a mulching film; covering the whole plant with an isolating net enclosure before the entering of the Chinese cabbage plant into an initial flowering stage, and inserting fixation rods on two sides of the isolating net enclosure respectively, fixing the isolating net enclosure on the fixation rods; when daily flowering quantity of the Chinese cabbage plant reaches more than 20, putting 2 bumblebees into the isolating net enclosure of each Chinese cabbage plant, then imbedding the mouth of the isolating net enclosure to the underground; after putting the bumblebees, spraying a mixed solution of 3%-4% of salt and 500 times of borax by mass every morning.