The invention provides a banana storage and transportation preservative which is prepared by mixing a plant extracting solution and auxiliary materials by weight ratio. The plant extracting solution is prepared by portulaca oleracea, licorice root, cordate houttuynia, camphor tree leaves, lemon leaves, hyssop, litsea cubeba, fructus forsythiae, thyme, cassia barks and wormwood through water extraction. The auxiliary materials are obtained by mixing sucrose fatty acid ester, chitosan, xanthan gum, potassium sorbate and lysozyme. The invention also provides a method for preparing the banana storage and transportation preservative. Compared with the prior art, the banana storage and transportation preservative is mainly prepared by synthesizing the plant extracts in proportion, addition of chemical drugs is decreased or completely avoided, the preservative is safe and environmentally friendly and has very good sterilization and preservation effects, fruit rotting caused by harm of multiple fungi or bacteria is prevented, and the preservation time is long. In addition, the materials of the sterilizing preservative are convenient to obtain, the raw material cost is low, a process is simple, and the banana storage and transportation preservative has wide application significance and market prospect.