The work aims to improve the adaptability performance between tinplate and lacquers and study the effect of preheating treatment for eliminating eye holes on the surface film and wettability of tinplate. Chronopotentiometric method, X-ray photoelectron spectroscopy, thermogravimetric differential thermal test and surface contact angle analysis were used to evaluate the changes in the passivation film and oxidation film on tinplate surface before and after preheating treatment and the wettability performance was analyzed by surface energy. After preheating treatment at 120 ℃ for different time, the chromium content in the passivation film increased from 4.30 μg/cm2 to 5.16 μg/cm2, and the ratio of Cr(OH)3/Cr2O3 decreased significantly, leading to that the electroactive Cr2O3 produced by dehydration and condensation of Cr(OH)3 was detected. The oxide film content was reduced from above 1.5 mC/cm2 to about 0.6 mC/cm2, with composition further oxidized to SnO2, which could not be reduced by cathode, thus reducing the content of oxidation film that could be detected. Meanwhile, the water contact angle quickly decreased from 86° to about 65°, and the surface energy value increased from 37.5 mN/m to 50 mN/m, which indicated that the surface wettability was greatly improved for water and other polar mediums by preheating treatment. The preheating treatment before tinplate coating changes the composition and content ratio of passivation film and oxidation film on tinplate surface, reduces the water contact angle, improves the surface energy and enhances adaptation range for lacquers, which is conductive to the stable spread of lacquers and provides a technical direction for controlling eye holes on tinplate.