Abstract: Admissibility has an independent value in international sports arbitration, and its role in restraining the expansion of compulsory procedures is crucial. Currently, the conceptual scope of admissibility is vaguely defined by academics, and the application of adjudication standards in international sports arbitration is not yet clear. This paper, through, case analysis, comparative research and other methods, identifies its conceptual connotation and analyze its jurisprudence cases and difficulties in order to build its theoretical foundation. It is found that the admissibility of international sports arbitration is different from the admissibility of jurisdiction and arbitrability and commercial arbitration, featured with unique attributes. The inadmissibility mainly includes overdue appeal, non-exhaustion of internal remedies, no appealable decision and invalid application. The difficulty in practice stems from the dual relationship between "appealable decision", "exhaustion of internal remedies" and jurisdiction. And its theoretical basis integrates the theory of procedural justice, the theory of arbitration autonomy and the demand for autonomy in the sports industry, forming a unique logical framework.