The invention provides a var. Denneanum extract and a preparation method thereof, wherein the preparation method comprises firstly extracting by using an alcohol-water dual extraction method, and then condensing and drying to obtain the var. Denneanum extract. The invention further provides formula particles of the var. Denneanum and preparation method thereof. According to the preparation method of the var. Denneanum extract provided by the invention, various effective components of the var. Denneanum can be relatively fully extracted by organically combining condition parameters of extraction technology, transfer rate of the dendrobium phenol can reach to more than 80 %, thereby not only ensuring consistency of the var. Denneanum extract and pharmacodynamic material base of original medicinal materials, thus being beneficial to the preparation of formula particles in a later stage, but also effectively preventing wastes of medicinal material resources.