The invention discloses a high-unloading slot composite-incision demolition blasting method for a reinforced concrete cooling tower, and relates to a demolition blasting method for the reinforced concrete cooling tower. The demolition blasting method comprises the following steps: pre-demolishing an internal sprinkling platform and an external ladder of the reinforced concrete cooling tower to be demolished by blasting; arranging a composite blasting incision including a rectangular herringbone pillar area, a trapezoidal ring beam area, an acute triangular directional window and a high unloading slot on the lower part of the tower body, wherein the high unloading slot and the directional window are mechanically arranged so as to ensure the construction precision; drilling at the herringbone pillar and a ring beam which is locally required to be loosened by blasting (a ring beam loosening area is constructed by a mechanical method and a blasting method), filling explosive, fencing, and strengthening blasting of a millisecond delay blasting network through non-electric bidirectional multi-point excitation. By the demolition blasting method, the falling direction can be accurately controlled, the number of boreholes and the amount of the explosive can be greatly reduced, the collapsing disintegration degree and the touchdown impact state of the tower body can be regulated and controlled, and the touchdown vibration can be effectively controlled.