The utility model discloses an effective environment-friendly and energy-saving modifying furnace of bulk curing barn heating equipment. The furnace comprises a furnace body, grate bars, an ash removing opening, a coal adding opening, a primary gas supply pipe, a blower, a secondary gas supply pipe, an annular air pipe, radiating fins and hot air outlets, wherein the radiating fins are arranged on the top of the furnace body, the grate bars are arranged between the ash removing opening and the coal adding opening; one end of the primary gas supply pipe is communicated with the blower and the other end of the primary gas supply pipe is communicated with the lower part of the furnace body; an on-off valve I is arranged on the primary gas supply pipe; the annular air pipe is arranged on the inner side of the upper end of the furnace body; one end of the secondary gas supply pipe is communicated with the annular air pipe and the other end of the annular air pipe are communicated with the blower; an on-off valve II is arranged on the secondary gas supply pipe; a plurality of air outlets which are uniformly distributed are formed in the inner side of the annular air pipe. According to the furnace, coal ash which is not fully combusted, gas and fresh air can be fully mixed, and the best secondary combustion effect is achieved.