The invention relates to a feed production system and process for a pregnant sow. The feed production system comprises a material distributing bin, a first material mixing mechanism, a second materialmixing mechanism, a crushing mechanism, a conditioning mechanism and a forming mechanism, which are sequentially connected, and further comprises a material storage bin, wherein the material storagebin comprises a first sub-bin and a second sub-bin which is isolated from the first sub-bin; the first sub-bin is used for storing magnesium sulfate powder; a magnesium sulfate weighing mechanism is connected to an outlet of the first sub-bin; the magnesium sulfate weighing mechanism is provided with a magnesium sulfate feeding outlet and a magnesium sulfate recovery outlet; the magnesium sulfatefeeding outlet is connected with an inlet of the first material mixing mechanism; a magnesium sulfate recovery mechanism is connected to the magnesium sulfate recovery outlet; and an outlet of the second sub-bin is connected with an inlet of the material distributing bin. Compared with the prior art, the feed production system and process disclosed by the invention can separately and accurately control the addition of magnesium sulfate, and can improve the mixing uniformity of the magnesium sulfate in a feed, so that the number of living piglets born by the pregnant sow can be increased, the labor stage of the pregnant sow can be shortened, and the birth weight of each of the piglets is increased.