Tribological properties are found to change with microstructure. In Ni-P amorphous alloy, annealing conditions were varied with laser irradiation parameters such as scanning speed and laser power. The increase in hardness affected by scanning speed. A peak of hardness was observed as the function of scanning speed. This is because, the formation of nanoscopic composite structure by distribution of crystalline Ni3P compounds in amorphous matrix is the hardest structure.