The invention belongs to the technical field of sesame breeding, and particularly relates to a method for efficiently creating sesame mutants with an ethylmethane sulfonate (EMS) mutagenic agent on a large scale. The method includes the steps that sesame seeds are treated with the EMS mutagenic agent, the seeds are planted, seedlings are transplanted, and the mutants are obtained. According to the method, by optimizing EMS treatment conditions, the mutation efficiency is significantly improved; meanwhile, by carrying out material planting and character observation with single plants and single strains as the unit, the mutant character survey efficiency and accuracy can be significantly improved. The method further has the advantages that the method can be applied to sesame mutant library establishment and directly applied to new variety breeding, various types of mutants can be obtained, and genetic backgrounds are clear and consistent and bring convenience to gene cloning. In general, the method can overcome the technical bottlenecks of good germplasm deficiency, low germplasm creating efficiency and the like in sesame breeding to some extent, and a material foundation can be laid for breeding of good new verities.