The galvanic corrosion behavior of Ti-15-3 titanium alloys and MT700/603B carbon fiber reinforced resin composites in alternate salt spray environment was studied. The effects of carbon fiber surface state， gap width and corrosion time on corrosion sensitivity and corrosion characteristics were analyzed. The results show that titanium alloy suffers the most serious degradation when the gap width is 0.06 mm. Compared with crevice corrosion， the corrosion weight loss rate and corrosion oxide area of galvanic corrosion are significantly larger under the same corrosion conditions， which indicates that the corrosion degree of galvanic corrosion is more destructive than crevice corrosion. The corrosion damage is more drastic in Cr region with nonuniform distribution.