Demarcation of the international boundary between India and Tibet was an important strategic event. The reference material studied here gives details about the tripartite “Simla Conference” and its outcomes which was started on 6th of October 1913 and ended in July 1914 at Simla the summer Capital of India. The conference was chaired by Sir Henry McMahon, British Indian plenipotentiary and the other two were lvan Chen representing China and Lochen Shatra, a leading minister of the Govt of Dalai Lama. These documents also throw light on the “McMahon Line” formed by the boundary agreement signed by India and Tibet given name on the name of sir Henry McMahon. Its prominent geographical fixation and demarcation which were agreed upon and resultantly signed by the representatives of India, China & Tibet, however have never been respected by China since inception.