The invention discloses a freeze-dried kumquat slice. A preparation method of the freeze-dried kumquat slice includes pretreatment, pre-freezing, sublimation drying, vacuum drying and pit removal by oscillating. As raw materials are directly freeze-dried without natural air drying and hot air drying, original nutritional ingredients of the raw materials are retained to the greatest extent; sublimation drying is carried out in four stages to maintain the color and luster of the raw materials to the greatest extent; no additives are added during processing, and the original flavors of the raw materials are retained. The water content of the prepared freeze-dried kumquat slice is less than 5%, microbial reproduction is not facilitated, and product storage is facilitated. Uniform honeycomb structures are formed between freeze-dried raw-material cells, so that the product has good reconstitution properties and brittleness and can be used directly or after crushing as food and raw materialsof food and drugs. The industrial value of kumquats can be improved, and inconvenience of storage, transportation and circulation of the kumquats in the harvest period can be avoided.