Based on the marine environment of Shipborne aircraft in service, the accelerated corrosion test was carried out for hot air leveling lead-free tin sprayed printed circuit board (PCB-HASL), which revealed the corrosion mechanism and characterized the macro/micro corrosion electrochemical behavior. According to the measured marine atmospheric environment data, based on the prepared accelerated corrosion test environment spectrum, the accelerated corrosion test was carried out for PCB-HASL. The polarization curve and electrochemical impedance spectroscopy of samples with different corrosion cycles were measured by electrochemical workstation, and the corrosion electrochemical mechanism and macro electrochemical characteristics were characterized; Scanning Kelvin probe technique was used to measure the distribution characteristics of Kelvin potential on the surface of samples with different corrosion cycles, and the micro area electrochemistry characteristics were characterized. During the 6th cycle of corrosion, the insulation resistance of PCB-HASL decreases greatly and reaches the critical state of failure; In cycle 0th-2nd, the self corrosion current density increased from 1.43 μA/cm2 increased sharply to 3.97 μA/cm2, the corrosion rate increases rapidly and corrosion is induced in local areas; In the 2nd-3rd cycle, the self corrosion current density decreases and the corrosion rate decreases; In the 3rd-4th cycle, the self corrosion current density increased slightly, the corrosion rate increased slightly, and the corrosion products fell off locally; In the 4th-7th cycle, the self corrosion current density decreases and reaches the minimum in the 7th cycle, which is 0.55 μA/cm2, decreased by 86% compared with the second cycle, showing obvious uniform corrosion characteristics. The variation law of Kelvin potential distribution and reciprocal of charge transfer resistance (1/Rct) with the accelerated corrosion test cycle is consistent with the variation law of self corrosion current density. The corrosion rate of PCB-HASL roughly increases-decreases-slightly increases-decreases with the accelerated test cycle, and gradually changes from local corrosion in the initial stage to uniform corrosion in the later stage. A relatively dense corrosion product layer is formed on the surface, which greatly reduces the corrosion rate.