A clear and simple proving method is given,for that ILS estimator equals 2SLS estimator to simultaneous equations econometrics model,while the structure equation is just right for identification.

• 针对联立方程计量经济学模型 ；在结构方程为恰好识别时 ；ILS估计和 2SLS估计的等价性 ；给出了一个清晰、简洁的证明方法 .