The invention relates to a Brassica campestris soilless cultivation method, and belongs to the technical field of soilless cultivation. The Brassica campestris soilless cultivation method includes the following steps: medium preparation, nutriment solution preparation, greenhouse equipment allocation, disc arrangement and soil filling, seed sowing and soil covering, watering and germination, planting preparation, and harvesting. A medium includes perlite, coconut chaff, straw powder, plant residue, saw dust, peanut shells, pig manure, earthworm cast, peptone, silkworm chrysalis meal, conch powder, and broad bean leaf chaff. The nutriment solution includes water, potassium sulphate, urea, sodium molybdate, mild alcohol, indolebutyric acid, gibberellins, ammonium molybdate, zinc sulfate, manganese sulfate, powdered rock phosphate, naphthylacetic acid, saccharose solution, ferment, wood vinegar solution, potassium silicate, jasmonic acid and bacillus subtilis powder. The Brassica campestris soilless cultivation method is rich in medium nutriment, is easy to promote, and is few in pest; and the obtained Brassica campestris is rich in nutriment, is good in taste, and is short in growth period.