The invention discloses a medical waste liquid treatment device and a treatment method. The medical waste liquid treatment device comprises a left box body and a right box body, wherein a motor shaftof a servo motor penetrates through the left box body and is connected with a carrying box; a carrying plate is arranged in an inner cavity of the right box body; a recycling bucket is arranged underthe carrying plate; a vertical plate is arranged at the top end of the carrying plate; four groups of electrical telescopic rods are arranged at the left side of the vertical plate along the horizontal direction; a crushing cone is arranged at the other end of each connecting rod; the top end, bottom end, front end and back end of the carrying box are respectively provided with a groove; a cover plate is hinged to each groove; liquid leaking holes are uniformly formed in each cover plate; clamp buckles are uniformly arranged at the edge of each cover plate; the top end, bottom end, front end and back end of the carrying box are respectively provided with a clamp groove which is matched with the corresponding clamp buckle; separating plates are uniformly arranged in an inner cavity of eachgroove; a stirring device is arranged under the carrying box; support legs are arranged at both sides of the bottom end of the left box body. The medical waste liquid treatment device has the characteristics that the centralized treatment effect is realized, the working efficiency is high, the environment-friendly effect is realized, and the like.