Provided is a method for intracellularly producing a large amount of a Cry protein in a Bacillus bacterium. A method for producing a Cry protein or a culture product comprising the Cry protein, comprising transforming a Bacillus bacterium with an expression plasmid incorporating a gene encoding the Cry protein operably linked to a regulatory region comprising a σA-dependent promoter or a σH-dependent promoter, and culturing the transformed cell, wherein the expression plasmid comprises a polynucleotide encoding a replication protein consisting of the amino acid sequence set forth in SEQ ID NO: 9 or a protein having an identity of 80% or more or more with the amino acid sequence of the replication protein and involved in replication initiation.