The principles of several detection techniques for hydrogen mapping widely used at present and it’s applications in the study of hydrogen permeation and hydrogen embrittlement were introduced, including atom probe tomography (APT), scanning Kelvin probe force microscopy (SKPFM), secondary ion mass spectroscopy (SIMS) and hydrogen microprinting technique (HMT), as well as thermal desorption mass spectrometry (TDS) technique used for the detection of hydrogen concentration. Then, the principles and characteristics of several detection techniques were summarized and their typical applications in the fields related to hydrogen were introduced briefly. APT and SIMS were used to obtain the hydrogen mapping in materials by directly detecting hydrogen with mass spectrometry. SKPFM got the hydrogen mapping by the surface potential changes induced by hydrogen. The principle of HMT was to characterize the hydrogen mapping through the distribution of Ag atoms on the specimen surface through a substitution reaction (H atom substituted Ag+ with Ag atom). As for thermal desorption technique, the hydrogen concentration at various traps and the bond strength between hydrogen atoms and traps at different sites were characterized by the sensitivity of desorption rates at constant heating rate to various traps. The spatial resolution of these techniques was from sub-nanometer to nanometer, micrometer and several micrometers and even millimeters. In addition, SKPFM had time resolution function. The application of these hydrogen detection techniques gives researchers an intuitive understanding on the microscopic distribution and aggregation state of hydrogen atoms in the material, thus providing a deeper understanding of the microscopic mechanism of hydrogen-induced delayed fracture. Finally, several common methods of detecting H concentration are mentioned.