This thesis involves the production and properties of concrete using recycled aggregate. The goal of the thesis itself is to explain the properties of a recycled concrete aggregate, which is created by demolishing buildings and the properties of concrete in conjunction with such and aggregate in fresh and solid state. In the introductory part od the thesis, the essential characteristics of recycled aggregate and concrete are stated, as is its impact on climate change. The following chapter includes an in-depth description of the production and properties of a recycled aggregate. The main section describes the properties of concrete with recycled aggregate in fresh and solid state and its impact on the environment. Recycled aggregate already has porosity and a more pronounced roughness, therefore the workability of concrete with a recycled aggregate is lower than the volumetric mass of concrete with a natural aggregate and this causes a lower compressive strength of concrete. All tests suggest that the differences in the properties of concrete depend immensely on the scale to which natural aggregate is replaced with a recycled one. The application of such concrete in Croatia is described at the very end of this thesis.