The invention relates to a reliable method for inspecting and researching HIC (hydrogen-induced cracking) sample cracks. The method comprises the main experiment procedures as follows: (1) processingof an HIC sample; (2) cleaning and storage of the sample; (3) sample soaking; (4) oxygen removal and H2S introduction; (5) pH value determination; (6) continuous testing for 96 h in an H2S saturated state; (7) taking out of the sample; (8) nondestructive testing; (9) sample cutting; (10) grinding, polishing and sample section cutting; (11) evaluation of the sample; (12) selection of an auxiliary welding part; (13) welding; (14) snapping; (15) removal of an auxiliary part; (16) cleaning of the cracked sample and measurement of the depth and width of the cracking surfaces under a metallurgic microscope; (17) deep research of the section. The morphology of the cracking surfaces, including cracking and extension processes, can be directly observed. Dyeing of primary cracking surfaces can be realized through the heating process in a welding technology, and primary cracking surfaces and secondary cracking surfaces can be distinguished. All cracking surfaces can be displayed, missing detection of cracks is avoided, and the morphology and size of the cracking surfaces can be reflected completely.