A passivation film of excellent corrosion resistance and self repairability can be obtained on metal surface by adopting traditional chromate passivation treatment technology. However, since high toxicity of hexavalent chromium threatens the human’s health, the hexavalent chromium passivation process has been restricted in recent years, and current studies are focusing on development of new environmentally friendly chromium-free passivation technology. Existing chrome-free passivation process of hot-dip galvanized sheet can be basically classified into three types: inorganic passivation, organic passivation, inorganic/organic composite passivation. Mechanism and research progress of the three types of chrome-free passivation were introduced in detail. The existing preparation technologies of galvanized sheet surface chrome-free passivation film were elaborated, covering molybdate passivation, tungstate passivation, silicate passivation, phytate passivation, tannic acid passivation, organosilane passivation, organic resin passivation and inorganic salt/organic resin complex passivation. Characteristics of these chrome-free passivation technologies were summarized, and structural characteristics of the passivation film obtained by adopting different chrome-free passivation technologies were clarified. Advantages and disadvantages of various chrome-free passivation films were further analyzed by comparing with properties of chromate passivation films. Finally, the advantages of inorganic passivation and organic passivation were proposed for comprehensive utilization. Research and development of new environmentally friendly inorganic/organic compound passivation technology is proposed to be future development trend of chrome-free passivation technology of hot-dip galvanized steel sheet.