The polar climate environment is special, and metal materials may be exposed to ice cover for a long time. Herein, the effect of variable- and constant-temperature on the corrosion behavior of a Ni-Cr-Mo-V high-strength steel under ice cover conditions was studied. Therefore, an indoor simulation test procedure was proposed as follows: periodic corrosion tests beneath ice cover were conducted at variable temperatures ranging from -45 to -5 ℃ for one month, meanwhile the corrosion tests beneath ice cover at constant temperatures in the range of -5 and -45 ℃ were tacked as comparison. The results show that under the ice cover, the corrosion rate of high-strength steel increases with the increase of temperature; while the variable temperature has a relatively small impact on the corrosion morphology of high-strength steel; Electrochemical test results reveal that the capacitance arc radius of high-strength steel is relatively large, with a small range of variation. At low temperature -5 ℃, its self-corrosion potential is the lowest, but the difference is not significant compared to those by variable temperature conditions; XRD and Raman spectroscopic analysis indicate that the corrosion products are composed of α-FeOOH, β-FeOOH, γ-FeOOH, and Fe₃O₄/γ-Fe₂O₃. The temperature ranges from -45 ℃ to -45--5 ℃, and then to -5 ℃, the spicies of phase for corrosion products are showing an increasing trerd.