PROBLEM TO BE SOLVED: To provide a method for efficiently transform an orchid, especially a member of the genus Cymidium with a particle bombardment (biolistic or microprojectile bombardment). SOLUTION: This method is to carry out genetic manipulation of an orchid using a DNA construct containing an expression cassette. The construct contains a transcription initiation region and a peptide coding region located on the downstream side of the transcription initiation region under the regulation of transcription in the direction from 5' to 3' and the method includes the following steps: (a) a step for culturing a primary protocorm-like body(PLB) of the orchid in a liquid culture medium and inducing a secondary PLB, (b) a step for arranging a PLB containing both the primary PLB and the secondary PLB on the surface of a target, (c) a step for physically accelerating a far smaller microprojectile than cells of the PLB in the PLB, (d) a step for inducing the PLB subjected to bombardment in a liquid culture medium so as to form a proliferating PLB capable of forming a shoot and (e) a step for regenerating the shoot and thereby producing a cloning transgenic plant.
