The invention discloses ellipsoidal milk substitute milk powder for suckling pigs and a preparation method thereof. The ellipsoidal milk substitute milk powder comprises the following raw materials: concentrated whey protein, whey powder, whole milk powder, white sugar, cheese, sodium alginate, sodium carboxymethylcellulose, lysine, methionine, tryptophan and multi-vitamin; the particle diameter of the ellipsoidal milk substitute milk powder is 2.0 to 12.0mm; the ball height is 1.4 to 6.0mm. The method comprises the following steps: adding and sufficiently mixing the raw materials in proportion, so as to form a powder semi-finished product, then ensuring that the semi-finished product passes a compaction rolling-granulating system, so as to obtain a mixture of ellipsoidal particles and powder, and ensuring that the mixture passes a classifying screen, so as to obtain the ellipsoidal milk substitute milk powder (as shown in Figure 3). The method solves the problem that the necessary circular mould-press roll granulating system in the current feed industry cannot manufacture substitute milk powder into powder particles, successfully manufactures the formula milk substitute milk powder semi-finished product into ellipsoidal particles through the compaction rolling-granulating system, and realizes the convenience operation that the milk substitute milk powder can be used for directly feeding the suckling pigs in pig farms.