Observing recently GATS (The General Agreement on Trade in Services) cases, one fourth cases are relevant to non-discrimination regulations under GATS-Article 2 and 17. While applying to non-discrimination regulations of GATS, a essential condition for the Panel or Appellate Body, before considering whether Members' domestic measures in question are obstacles to international services market, is to determine whether foreign services and services suppliers and domestic services and service suppliers are 'like services' and 'like service supplier'. For 'like services and service suppliers' is a crucial requirement of non-discrimination regulations under GATS, finding out how to apply to 'like services and service suppliers' in WTO dispute settlements is an important research topic. Issues related to 'like services and service suppliers' include: how to determine 'like services' and 'like service suppliers'; how to decide whether the services and service suppliers through different supply modes are like services and like service suppliers; whether 'like services' and 'like service suppliers' should be calculated application or selected applicaiton. Notwithstanding the requirement of non-discrimination principles- 'like services and service suppliers' exists plenty problems, GATS did not define the meaning of 'like serivces' and 'like service suppliers', neither did GATS dispute cases clarify the application problems of 'like services and service suppliers'. In order to resolve issues of 'like services and service suppliers', firstly, the article discusses what issues are caused from applying to 'like services and service suppliers', and what factors make 'like services and services suppliers' so hard to explain. Then, the article researches how GATS cases apply to 'like servies and service suppliers'. In the third part, the article analyzes GATT (The General Agreement on Tariff and Trade)/WTO cases regarding 'like products'. Finally, by comparing the dispute cases of GATS and of GATT/WTO, the article demonstrates possible resolusions to the issues of 'like services and service suppliers'.