The selective laser melting (SLM) process of AlSi10Mg alloy is prone to pore defects and surface spheroidization, which can be mitigated through laser remelting treatment. This study focuses on three common pore defects—lack of fusion, gas holes, and keyholes—in AlSi10Mg alloy produced by SLM. The impact of remelting power on the density, surface roughness, and melt pool depth of the samples was examined to determine the optimal remelting power. The results show that the un-melted AlSi10Mg alloy power is remelted using laser remelting treatment, the lake of fusion defect can be eliminated, the keyhole and gas hole defects can be decreased, and the optimal remelting power is different for different pore defects. In addition, the laser remelting treatment can improve the surface morphology of the samples, eliminate the surface spheroidization phenomena and reduce the surface roughness.