The invention discloses a continuous braising water machine and a continuous grain cooking system and method, and relates to the technical field of wine-brewing production. During continuous water braising, the transmission rate of a chain plate is controlled to control the grain braising time and discharging, so that a mechanical grain braising process is realized, and the manpower is saved; and in a single-shift production process, grain braising water is always kept in the braising water machine and does not need to be discharged, so that the sewage discharge is reduced by 70% or above in comparison with the mode that braising water in a cooking pot is discharged every time. The continuous grain cooking system comprises the continuous braising water machine, and as all functional devices are continually connected, the problems that traditional wine brewing and grain cooking equipment is discontinuous, low in mechanical degree, much in manual demand and low in cooking efficiency are effectively solved, and the continuous grain cooking system can be used for cooking 7 tons of food per h, and therefore, is particularly suitable for large-scale wine-brewing production. The continuous grain cooking method is based on the continuous grain cooking system and utilizes waste heat in the process to preheat grains, so that the energy consumption is reduced, and the cost is lowered.