The invention discloses a bottom cap self-opening type garbage collection box and belongs to the technical field of garbage collection boxes. The technical effect of providing the garbage collection box which is clean, environmentally friendly and safe and has the bottom cap automatic opening function is achieved. According to the technical scheme, the bottom cap self-opening type garbage collection box comprises bottom cap opening and closing motion mechanisms, a box body and a bottom cap; a garbage throwing-in opening is formed in the top of the box body; wedge-shaped supporting blocks used for supporting the box body are arranged on the two sides of the box body, and bottom openings are formed in two sides of the box body; the bottom cap is arranged at the bottom of the box body and connected with the box body through torsional spring hinges; the torsional moment of the torsional spring hinges is no smaller than the torsional moment of the self weight of the bottom cap; and the two bottom cap opening and closing motion mechanisms are arranged in the middles of the two sides of the box body correspondingly. The bottom cap self-opening type garbage collection box is used for garbage collection.