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The results of the corrosion resistance of hot-dip galvanized coatings obtained on bolts made of steel grade 23MnB4 have been presented in the paper. The bolts were subjected to various treatments (heat, mechanical and chemical) before application of the zinc coating. Comparative evaluation of corrosion resistance of galvanized bolts was performed by accelerated corrosion tests in salt chamber and using electrochemical methods. The bolts were exposed to an atmosphere of neutral salt spray according to standard ISO 9227:2012 and the following methods: linear polarization and potentiodynamic cyclic voltammetry according to PN-EN ISO 10271:2012. In order to correlate corrosive environment of the tests, the 5% neutral salt solution was used at temperature 35°C. Results of the study were related to the results obtained for the bolts without zinc coating.It was found that the tested zinc coatings on the bolts are leaky and have relatively short-term corrosion protection. The surface preparation of bolts before hot-dip galvanizing and the centrifugation of excess zinc after process affected the results of corrosion tests. Therefore, in order to improve the quality of the anti-corrosion coatings on the bolts the further research is recommended in the field of the surface preparation before hot-dip galvanizing.

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