The invention discloses a lactobacillus effervescent tablet, which is prepared from 1 to 15 portions of lactobacillus powder, 20 to 50 portions of auxiliary materials, 10 to 30 portions of acid sources, 11 to 30 portions of sodium bicarbonate, 2 to 35 portions of disintegrating agent and 0.2 to 2.5 portions of lubricant. The effervescent tablet transmits lactobacillus to various parts of the uterus after effervescence through an acid-base reaction, increases the effective contact range of the lactobacillus and the uterus, makes a larger area of the lactobacillus adsorbed and set by a mucous membrane of the uterus, avoids the use of ointment, a suppository and a liquid preparation, overcomes the defect that the medicine can be only sent to the bottom and the side wall of the uterus, and not only achieves the aims of treatment and prevention but also reduces in vivo antibiotic residue.