Owing to the high cost of cobalt, the widespread application of FeCrNiSi-based high-entropy alloy coatings in marine environments remains constrained. Therefore, in this work, cobalt-free FeCrNiSi 0.5Mo x ( x=0.4,0.7,1.0) coatings were deposited onto Q235 steel substrates via laser cladding. Microstructural analysis reveals that increasing Mo content intensifies interdendritic segregation, forming dark dendrites (DD) and light dendrites (LD). The resultant micro-galvanic effect between these phases initiates corrosion at body-centered cubic (BCC) sites, accelerating localized degradation. Among these coatings, Si 0.5Mo 0.4 exhibits optimal corrosion resistance. Its oxide film further enhances wear resistance, reducing the wear volume to 14.17% of the substrate.