The invention discloses a spice nano-microcapsule and a preparation method thereof. Raw materials of the spice nano-microcapsule comprise spices and a wall material, wherein the wall material is a mixture of Arabic gum, sodium caseinate, maltodextrin, beta-cyclodextrin, modified starch and glucose in a mass percentage of (5%-15%):(5%-20%):(20%-40%):(5%-15%):(20%-40):(5%-15%). According to the spice nano-microcapsule and the preparation method thereof, Arabic gum, sodium caseinate, maltodextrin, beta-cyclodextrin, modified starch and glucose are mixed and used, and are limited in ratio, an emulsifier, namely sucrose ester, and the wall material in a mass ratio of (1:8)-(1:20) are also added, and a membrane emulsifying device is used at the same time, so that the evenness, the encapsulation rate and the dispersity of the microcapsule are improved; moreover, by means of SEM (scanning electron microscope) representation, the surface topography of the microcapsule is in a smooth spherical shape, the uniformity and the dispersity are good, the encapsulation rate of the microcapsule is high, and reaches up to 50% or more, and the loading capacity reaches 25% or more; the spice nano-microcapsule is quite suitable for spices with high volatility.