The invention discloses an evaporator core body. The evaporator core body comprises vertically-arranged flat tubes and corrugated fins arranged among the flat tubes, wherein each corrugated fin consists of an upper section and a lower section and the wave pitch of the upper sections of the corrugated fins is smaller than the wave pitch of the lower upper sections of the corrugated fins. The evaporator core body has the beneficial effects that the wave pitch of the lower sections of the corrugated fins is larger than the wave pitch of the upper sections of the corrugated fins, and since the wave pitch of the lower parts of the corrugated fins is increased, the condensate water can be drained more easily, the condensate water flowing from the upper parts of the corrugated fins can be prevented from generating water bridges at the lower parts of the corrugated fins, so that the space at the lower part of the evaporator is large enough so that air flow as much as the air flow passing through the upper region of the evaporator can pass; the ventilating uniformity of the evaporator core body is improved, the surface temperature difference of the core is relieved, the refrigeration performance is improved, and meanwhile, a frosting problem of the evaporator core body can be solved.