To provide a concrete block which exerts an environmental conservation function.

The concrete-stacked block is integrally formed of a skeleton 1 made of water retaining concrete, a head 2 made of water permeable concrete, and a plant epiphytic layer 3 made of a material effective for environmental conservation. A retaining wall constructed by using the concrete-stacked blocks thus formed functions to gradually evaporate retained water absorbed from a front surface of the block according to variation in ambient temperature and moisture, to thereby restrain the temperature from rising by virtue of heat of evaporation. The epiphytic layer helps adhesion of seeds and spores of plants, and water content supplement by evaporation contributes to budding and growth of plants.