To provide a permeable block which serves as a paving block for use in a sidewalk etc. or a river, which suppresses a heat-island phenomenon, that is, a temperature rise caused by reflected heat in summer, which brings about warmness in winter, which makes weeds hardly grow from lower soil ground, which prevents the elution of harmful matter, and which improves the propagation of bacteria etc.

Incinerated ash, construction sludge and soil as industrial waste are utilized as materials for the permeable block. The incinerated ash and a cement solidification material, or the incinerated ash, (inorganic) soil sludge and the cement solidification material are mixed together and solidified. Thus, a solidified material brings about the action of preventing the elution of the harmful matter, and a porous shape is formed at the stage of solidification. Consequently, the solidified material is constituted like activated carbon so as to obtain water permeability and water retention.