The invention discloses a rice blast disease-resisting protein, a coding gene and an application thereof. The protein provided by the invention is following (a) or (b): (a) a protein composed of amino acid sequences shown in the sequence 2 in the sequence table; (b) a protein obtained by substituting and/deleting and/adding one or more of amino acid residue for the amino acid sequence shown in the sequence 2 and deriving from the (a) related to plant blast disease resistance. The PID3-A4 protein and the coding gene provided by the invention can be used for cultivating a new blast disease-resisting plant variety, particularly, a variety showing resistance for blast disease caused by at least one of following Magnaporthe oryzae microspecies: JS2001-108-1, Zhong10-8-14, 97-27-2, 03-10-66-1, 07-31-1-2, 03-10-76-3, 10-25-1-1, 10-32-2-1, 03-11-37-1, 07-55-1-1, 10-47-9-2, 10-120-21-2, 07-21-1-1, 10-62-2-1, 07-26-22, 09-87-2-1, Y34, 99-26-2, CH706 and 99-20-2. The protein is beneficial to improve rice variety and has an important significance for enlarging crop planting range and improving crop yield.