In this paper, a hot-dip zinc specimen of CM series steel was used as the test material. First, for the accelerated salt spray corrosion test, the hot-dip zinc was sprayed with a 5% NaCl solution at a constant temperature of 35℃ and photographs were clicked to record the state of the surface. Next, an electrochemical polarization test was performed in a seawater electrolyte, and the zinc coating was observed using SEM to investigate the corrosion mechanism. In addition, the morphology of the hot-dip zinc material was observed using a three-dimensional digital microscope and a further electrochemical polarization experiment was performed in an anaerobic bacterial environment. The results of the accelerated salt spray test indicated that the corrosion rate decreased with an increase in time; this occurred mainly because the corrosion product film inhibited the corrosion anode and cathode processes (passivation platform). Experiments under anaerobic conditions showed that the passivation platform was formed when the bacteria grew to their peak. This was mainly due to the formation of dense ZnS corrosion products on the electrode surface as these products formed a continuous and complete corrosion product film. Hot-dipped zinc products containing 99.99% pure zinc as the raw material show high corrosion resistance in the marine environment because of the protection of the corrosion products and the zinc-iron alloy layer. The salt spray and electrochemical polarization tests can be used as quick methods to evaluate the corrosion resistance of zinc coatings.