To investigate the corrosion characteristics and anti-fouling properties of Cu-Mn cladding layers with different Mn contents, the laser cladding technique was used to prepare Cu-Mn cladding layers with homogeneous composition and low dilution rate. Electrochemical tests, salt spray corrosion experiments, corrosion morphology observations, and copper ion release tests were conducted to investigate the corrosion characteristics of Cu-Mn cladding layers with different Mn contents in 3.5wt% NaCl solution. The effect of Mn on corrosion products and copper ion release rate was particularly studied. Results show that the corrosion resistance of cladding layers is decreased with increasing the Mn content during the electrochemical tests. In the salt spray corrosion experiments, the corrosion degree of the Cu-Mn cladding layer is deepened with increasing the Mn content, and the average mass loss is increased. The corrosion morphology of cladding layers after electrolytic corrosion was observed. Compared with those of Cu-Mn cladding layer with low Mn content, the corrosion products generated from Cu-Mn cladding layer with high Mn content have more sparse structure, the number of crack holes is larger, and the corrosion products are easier to peel off. In the copper ion release test, all cladding layers can inhibit the growth of sea creatures. The higher the Mn content, the greater the copper ion release rate, presenting great application potential in anti-fouling materials.