Seafloor hydrothermal activities are involved with extreme conditions. Therefore traditional deep-sea investigation methods can not be satisfied with the investigation demand. Recent technologies, such as visual-sampling technology, submersible technology, in-situ monitoring technology and sampling with fidelity technology and experimental simulation technology, have been developed and widely used. Based on the advances in the investigation technologies associated with modern seafloor hydrothermal activities, the development of the investigation technologies in this field should be paid much attention to by our country.