The invention discloses a traditional Chinese medicine sustained release preparation for treating diabetes and complications thereof and a preparation method thereof. The traditional Chinese medicine sustained release preparation is prepared from a traditional Chinese medicine raw material extract, a sustained-release material and other pharmaceutically acceptable accessories. The traditional Chinese medicine sustained release preparation disclosed by the invention is prepared by adding a certain amount of sustained-release material and other pharmaceutically acceptable accessories by means of scientific design. By virtue of the raw materials and the preparation method disclosed by the invention, the prepared sustained release preparation has good stability, avoids the loss of volatile active ingredients, reduce the frequency of administration, maintain stable blood concentration, prolong the maintenance time of the active ingredients and the reduce the side effects, and the controlled release drug preparation further has the advantages of high bioavailability, obvious curative effect, and capability of reducing the frequency of administration and improving the compliance of patients, etc.