Al2O3 thin- wall ceramic is formed by laser engineered net shaping and distribution of coaxial powder is obtained using tapes. A function is found to be related to the distribution of powder density. Based on this function, the influence of laser spot size and laser power on the surface morphology of thin-wall Al2O3 ceramic is analyzed. The results show that the distribution of coaxial feeding powder is in keeping with the double Gaussian distribution. Laser spot size directly affects the powder utilization, and thereby affects the surface morphology of thin- wall parts. There is a Gaussian integral function between the laser spot size and the quantity of powder irradiated by laser beam. The results also demonstrate that high laser power can weaken the influence of powder on laser energy distribution, which can improve the surface morphology of thin- wall parts, but the surface morphology is bad if the laser power is too high. The relative density of the Al2O3 ceramic is up to 99.72% with suitable process parameters.