The present invention provides an automated experiment apparatus and an automated experiment method using the same for putting a sample into a pressure vessel and automatically performing a chemical and/or physical reaction of the sample under a predetermined temperature and pressure. According to the embodiments of the present disclosure, it is possible to automatically perform an experiment from the beginning to the end without intervention of an user. As a result, it is possible to prevent a risk of gas leakage and human exposure to a harmful gas due to a manual operation. The apparatus comprises a controller which is configured to automatically perform a reaction process under a predetermined temperature and pressure in a state in which a sample holding member is air-tightly fixed to a pressure vessel and the sample is accommodated in a sample receiving chamber of the pressure vessel.