In the cement industry, the search for more economical binders using waste and natural resources has become crucial to overcome the shortage of Portland cement and respect the environment. Algeria has significant potential in natural resources such as perlite, a volcanic rock that can be finely ground and used as an active mineral additive in the production of cement to reduce the release of CO2. This study examines the benefits and feasibility of using perlite as a partial substitute for cement in mortar manufacturing, with volume substitution rates of 5%, 10%, 15%, 20% and 25%. Tests were carried out to evaluate physical, mechanical and thermal behavior, including consistency, setting time, workability, capillary absorption, mechanical strength and thermal conductivity. The results obtained indicate that the presence of perlite increases the water requirement, accelerates the setting time in the fresh state and improves capillary absorption in the hardened state. In the long term, the mortar containing perlite develops mechanical resistance greater than that of the reference mortar (0% perlite) which increases proportionally with the increase in the percentage of perlite used. In addition, perlite-based mortar presents interesting thermal and physical properties, highlighting the advantages of perlite as a thermal insulator and the interest in reinforcing this ecological addition.