The work aims to study the influence of temperature on the critical relative humidity of pitting corrosion and re-passivation under dry and wet cycle of droplets, and to analyze the formation mechanism of pitting by observing morphology. The effect of temperature on pitting corrosion of 430 stainless steel in dry and wet cycles was studied by multi-droplet potential monitoring. Secondly, statistical method was used to analyze the characteristic parameters of pitting corrosion of 430 stainless steel during the dry and wet cycle, such as critical relative humidity of pitting corrosion, repassivation and corresponding critical chloride ion concentration. Then, the characteristic parameters such as the depth and diameter of the pitting pit were statistically analyzed by laser confocal microscopy. Finally, the potentiodynamic polarization curves of 430 stainless steel in MgCl2 solution at different temperatures were compared. As the temperature rose from 10 ℃ to 50 ℃, the probability of pitting corrosion increased from 5/35 to 25/35, the average critical relative humidity of pitting corrosion rose from 55% to 63% and the corresponding chloride ion concentration decreased from 7.4 mol/L to 6.4 mol/L; while the average critical relative humidity of repassivation increased from 74% to 91% and the corresponding chloride ion concentration decreased from 5 mol/L to 2.5 mol/L. Temperature rise accelerates the pitting growth of 430 stainless steel, but inhibits repassivation. Morphological analysis shows that with the increase of temperature, the morphology of pitting pits accelerates from lateral growth to pit depth.