The invention relates to removal of excrement and urine from animal houses, in particular to a harmless excrement-automatically-cleaned pig toilet. Each piggery comprises a lying area (1), a feeding area (2) and a defecation area (3), wherein the lying area (1) and the defecation area (3) are respectively located at the two sides of the corresponding piggery, the defecation area (3) is lower than the lying area (1), and the feeding area (2) is distributed on sidewalls of the corresponding piggery. The harmless excrement-automatically-cleaned pig toilet is located in the defecation area (3) and comprises a movable baffle (32), a micro-slit floorboard (31) and an excrement and urine gutter (33). During excrement cleaning, pigs are slowly driven out of the defecation area, so as to form a closed excrement cleaning space, and thus, the pigs, which like to lie in the defecation area or like to hog a scraping rake during excrement scraping, cannot be harmed; an activity space for the pigs is improved through changing a defecation space, namely the space of the pig toilet is occupied only when excrement cleaning is required to be carried out, and the space of the pig toilet can serve as the activity space for the pigs at other times.