Macrophytes are plants that grow partially or fully submersed in water. Considering their habitat and growth form they can be classified as submersed macrophytes, macrophytes rooted underwater with floating leaves, macrophytes with leaves above water and free-floating macrophytes. Term macrophyte includes species from very different and phylogenetically unrelated groups (spermatophytes, pteridophytes, bryophytes and charophytes). The most important traits that help macrophtyes to adapt to their habitat include aerenchyma, poor lignification, thin cuticle, increased submersed leaf surface, hydropotes and special enzymatic mechanism for carbon dioxide uptake. This paper reviews abiotic parameters that affect growth and occurrence of macrophytes (water transparency, water temperature, water nutrition content, substrate characteristics and water movements). Also, most common macrophyte species that occur in Croatia are classified by their habitats and in that classes the most important plant associations are described.