Porous ceramics were produced by mixing clay and ash of sago waste from the sago processing industry in Indonesia. The composition was prepared by adding an amount from 0 to 40 wt% of ash into the clay, and then the samples were milled for 6 h. The samples were dry pressed and sintered in the temperature range between 900°C and 1300°C. The influence of the ash content and the sintering temperature on the bulk density, firing shrinkage, and porosity was studied in detail. The results show that an amount of 10 wt% ash can be incorporated into the clay material without any appreciable effect on the bulk density and porosity of the samples sintered at 1000°C. It was found that if the amount of ashes is greater than 20 wt% and the sintering temperatures are lower than 1100°C, then the percentage of the porosity is greater than 30%. These results are important for optimization of the parameters of the technological processes for production of porous ceramics for various applications, each of which requires a specific porosity.