The invention discloses a flower black tea food as well as a preparation method and application of the food. The flower black tea food is prepared by the following steps: by taking plant flowers and black tea as raw materials, performing ultrafine grinding on flowers, mixing the flower powder and black tea powder in percentage by weight: 5-50% of flower powder and 50-95% of black tea powder, grinding, mixing and performing solid biological fermentation, performing water extractionthree times, performing centrifugal separation, filtering, merging the filtrate, concentrating to prepare a concentrated solution, and sterilizing, thereby obtaining the product. According to the preparation process disclosed by the invention, the defects in the prior art can be overcome, so that the dissolution rate is high, the conversion efficiency is high, losses are small, the utilization rate of the flowers and black tea is high, more new nutrition and functional components can be produced due to a biochemical reaction in the biological fermentation process, the application effects of the product are enhanced, the taste is improved, the quality is improved, and novel raw material products are provided for processing industries such as food products, condiments, soft drinks, wine processed products, nutrient supplement products, cosmetics and the like.